To see the other types of publications on this topic, follow the link: Water – Purification – Photocatalysis.
Journal articles on the topic 'Water – Purification – Photocatalysis'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Water – Purification – Photocatalysis.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Le Pivert, Marie, Nathan Martin, and Yamin Leprince-Wang. "Hydrothermally Grown ZnO Nanostructures for Water Purification via Photocatalysis." Crystals 12, no. 3 (February 22, 2022): 308. http://dx.doi.org/10.3390/cryst12030308.
Full textAbstract:
Semiconductor-based photocatalysis is a well-known and efficient process for achieving water depollution with very limited rejects in the environment. Zinc oxide (ZnO), as a wide-bandgap metallic oxide, is an excellent photocatalyst, able to mineralize a large scale of organic pollutants in water, under UV irradiation, that can be enlarged to visible range by doping nontoxic elements such as Ag and Fe. With high surface/volume ratio, the ZnO nanostructures have been shown to be prominent photocatalyst candidates with enhanced photocatalytic efficiency, owing to their being low-cost, non-toxic, and able to be produced with easy and controllable synthesis. Thus, ZnO nanostructures-based photocatalysis can be considered as an eco-friendly and sustainable process. This paper presents the photocatalytic activity of ZnO nanostructures (NSs) grown on different substrates. The photocatalysis has been carried out both under classic mode and microfluidic mode. All tests show the notable photocatalytic efficiency of ZnO NSs with remarkable results obtained from a ZnO-NSs-integrated microfluidic reactor, which exhibited an important enhancement of photocatalytic activity by drastically reducing the photodegradation time. UV-visible spectrometry and high-performance liquid chromatography, coupled with mass spectrometry (HPLC-MS), are simultaneously used to follow real-time information, revealing both the photodegradation efficiency and the degradation mechanism of the organic dye methylene blue.
2
Alalm, Mohamed Gar, Ridha Djellabi, Daniela Meroni, Carlo Pirola, Claudia Letizia Bianchi, and Daria Camilla Boffito. "Toward Scaling-Up Photocatalytic Process for Multiphase Environmental Applications." Catalysts 11, no. 5 (April 28, 2021): 562. http://dx.doi.org/10.3390/catal11050562.
Full textAbstract:
Recently, we have witnessed a booming development of composites and multi-dopant metal oxides to be employed as novel photocatalysts. Yet the practical application of photocatalysis for environmental purposes is still elusive. Concerns about the unknown fate and toxicity of nanoparticles, unsatisfactory performance in real conditions, mass transfer limitations and durability issues have so far discouraged investments in full-scale applications of photocatalysis. Herein, we provide a critical overview of the main challenges that are limiting large-scale application of photocatalysis in air and water/wastewater purification. We then discuss the main approaches reported in the literature to tackle these shortcomings, such as the design of photocatalytic reactors that retain the photocatalyst, the study of degradation of micropollutants in different water matrices, and the development of gas-phase reactors with optimized contact time and irradiation. Furthermore, we provide a critical analysis of research–practice gaps such as treatment of real water and air samples, degradation of pollutants with actual environmental concentrations, photocatalyst deactivation, and cost and environmental life-cycle assessment.
3
Bedia, Jorge, Virginia Muelas-Ramos, Manuel Peñas-Garzón, Almudena Gómez-Avilés, Juan Rodríguez, and Carolina Belver. "A Review on the Synthesis and Characterization of Metal Organic Frameworks for Photocatalytic Water Purification." Catalysts 9, no. 1 (January 7, 2019): 52. http://dx.doi.org/10.3390/catal9010052.
Full textAbstract:
This review analyzes the preparation and characterization of metal organic frameworks (MOFs) and their application as photocatalysts for water purification. The study begins by highlighting the problem of water scarcity and the different solutions for purification, including photocatalysis with semiconductors, such as MOFs. It also describes the different methodologies that can be used for the synthesis of MOFs, paying attention to the purification and activation steps. The characterization of MOFs and the different approaches that can be followed to learn the photocatalytic processes are also detailed. Finally, the work reviews literature focused on the degradation of contaminants from water using MOF-based photocatalysts under light irradiation.
4
Li, Yunzhang, Youjia Ma, Kan Li, Suhong Chen, and Dongting Yue. "Photocatalytic Reactor as a Bridge to Link the Commercialization of Photocatalyst in Water and Air Purification." Catalysts 12, no. 7 (June 30, 2022): 724. http://dx.doi.org/10.3390/catal12070724.
Full textAbstract:
The development of clean and sustainable teleology is vital to treat the critical environmental pollutants. In the last decade, the use of photocatalytic reactors has been widely reported for organic pollutants degradation. From photocatalysis’s application in environmental remediation, the primary technical issue to scientists is always the efficiency. The enhanced photocatalytic efficiency is mainly depended on the materials improvement. However, the design of photoreactors lags behind the development of photocatalysts, which strongly limit the widespread use of photocatalysis technology in environmental remediation. The nanoparticles separation, mass transfer limitation, and photonic efficiency have always been problematic and restrict the high photocatalytic efficiency of photoreactors. To overcome these bottleneck problems, the most popular or newfangled designs of photoreactors employed in air and water treatment has been reviewed. The purpose of this review is to systematize designs and synthesis of innovative TiO2-based photoreactors and provides detailed survey and discussion on the enhanced mechanism of photocatalytic performance in different TiO2-based photoreactors. The most studied photoreactors are the following: packed bed reactor, film reactor and membrane reactor, which have some limitations and advantages. A comprehensive comparison between the different photocatalytic performance of TiO2-based photoreactors is presented. This work aims to summarize the progress of TiO2-based photoreactors and provides useful information for the further research and development of photocatalysis for water and air purification.
5
Bielan, Zuzanna, Szymon Dudziak, Adam Kubiak, and Ewa Kowalska. "Application of Spinel and Hexagonal Ferrites in Heterogeneous Photocatalysis." Applied Sciences 11, no. 21 (October 29, 2021): 10160. http://dx.doi.org/10.3390/app112110160.
Full textAbstract:
Semiconducting materials display unique features that enable their use in a variety of applications, including self-cleaning surfaces, water purification systems, hydrogen generation, solar energy conversion, etc. However, one of the major issues is separation of the used materials from the process suspension. Therefore, chemical compounds with magnetic properties have been proposed as crucial components of photocatalytic composites, facilitating separation and recovery of photocatalysts under magnetic field conditions. This review paper presents the current state of knowledge on the application of spinel and hexagonal ferrites in heterogeneous photocatalysis. The first part focuses on the characterization of magnetic (nano)particles. The next section presents the literature findings on the single-phase magnetic photocatalyst. Finally, the current state of scientific knowledge on the wide variety of magnetic-photocatalytic composites is presented. A key aim of this review is to indicate that spinel and hexagonal ferrites are considered as an important element of heterogeneous photocatalytic systems and are responsible for the effective recycling of the photocatalytic materials.
6
Janczarek, Marcin, and Ewa Kowalska. "Computer Simulations of Photocatalytic Reactors." Catalysts 11, no. 2 (February 3, 2021): 198. http://dx.doi.org/10.3390/catal11020198.
Full textAbstract:
Photocatalysis has been considered future technology for green energy conversion and environmental purification, including carbon dioxide reduction, water splitting, air/water treatment, and antimicrobial purposes. Although various photocatalysts with high activity and stability have already been found, the commercialization of photocatalytic processes seems to be slow; it is thought that the difficulty in scaling up photocatalytic processes might be responsible. Research on the design of photocatalytic reactors using computer simulations has been recently intensive. The computer simulations involve various methods of hydrodynamics, radiation, and mass transport analysis, including the Monte Carlo method, the approximation approach–P1 model, and computational fluid dynamics as a complex simulation tool. This review presents all of these models, which might be efficiently used for the scaling-up of photocatalytic reactors. The challenging aspects and perspectives of computer simulation are also addressed for the future development of applied photocatalysis.
7
Xu, Pingfan, Siyi Huang, Minghua Liu, Yuancai Lv, Zhonghui Wang, Jinlin Long, Wei Zhang, and Haojun Fan. "Z-Schemed WO3/rGO/SnIn4S8 Sandwich Nanohybrids for Efficient Visible Light Photocatalytic Water Purification." Catalysts 9, no. 2 (February 17, 2019): 187. http://dx.doi.org/10.3390/catal9020187.
Full textAbstract:
Semiconductor photocatalysis has received much attention as a promising technique to solve energy crisis and environmental pollution. This work demonstrated the rational design of “sandwich” WO3/rGO/SnIn4S8 (WGS) Z-scheme photocatalysts for efficient purification of wastewater emitted from tannery and dyeing industries. Such materials were prepared by a combined protocol of the in situ precipitation method with hydrothermal synthesis, and structurally characterized by XRD, SEM, HRTEM, UV-vis DRS, and PL spectroscopy. Results showed that the Z-schemed nanohybrids significantly enhanced the photocatalytic activity compared to the single component photocatalysts. An optimized case of the WGS-2.5% photocatalysts exhibited the highest Cr(VI) reduction rate, which was ca. 1.8 and 12 times more than those of pure SnIn4S8 (SIS) and WO3, respectively. Moreover, the molecular mechanism of the enhanced photocatalysis was clearly revealed by the radical-trapping control experiments and electron paramagnetic resonance (ESR) spectroscopy. The amount of superoxide and hydroxyl radicals as the major reactive oxygen species performing the redox catalysis was enhanced significantly on the Z-scheme WGS photocatalysts, where the spatial separation of photoinduced electron–hole pairs was therefore accelerated for the reduction of Cr(VI) and degradation of Rhodamine B (RhB). This study provides a novel strategy for the synthesis of all-solid-state Z-scheme photocatalysts for environmental remediation.
8
Wang, Chuan, Hong Liu, and Yanzhen Qu. "TiO2-Based Photocatalytic Process for Purification of Polluted Water: Bridging Fundamentals to Applications." Journal of Nanomaterials 2013 (2013): 1–14. http://dx.doi.org/10.1155/2013/319637.
Full textAbstract:
Recent years have witnessed a rapid accumulation of investigations on TiO2-based photocatalysis, which poses as a greatly promising advanced oxidation technology for water purification. As the ability of this advanced oxidation process is well demonstrated in lab and pilot scales to decompose numerous recalcitrant organic compounds and microorganism as well in water, further overpass of the hurdles that stand before the real application has become increasingly important. This review focuses on the fundamentals that govern the actual water purification process, including the fabrication of engineered TiO2-based photocatalysts, process optimization, reactor design, and economic consideration. The state of the art of photocatalyst preparation, strategies for process optimization, and reactor design determines the enhanced separation of photo-excited electron-hole (e-h) pairs on the TiO2surface. For the process optimization, the kinetic analysis including the rate-determining steps is in need. For large-scale application of the TiO2-based photocatalysis, economics is vital to balance the fundamentals and the applied factors. The fundamentals in this review are addressed from the perspective of a bridge to the real applications. This review would bring valuably alternative paradigm to the scientists and engineers for their associated research and development activities with an attempt to push the TiO2-based photocatalysis towards industrially feasible applications.
9
Yan, Xin, Yuanyuan Wang, Bingbing Kang, Zhuo Li, and Yanhui Niu. "Preparation and Characterization of Tubelike g-C3N4/Ag3PO4 Heterojunction with Enhanced Visible-Light Photocatalytic Activity." Crystals 11, no. 11 (November 11, 2021): 1373. http://dx.doi.org/10.3390/cryst11111373.
Full textAbstract:
Water pollution caused by dye wastewater is a potential threat to human health. Using photocatalysis technology to deal with dye wastewater has the advantages of strong purification and no secondary pollution, so it is greatly significant to look for new visible-light photocatalysts with high photocatalytic ability for dye wastewater degradation. Semiconductor photocatalyst silver phosphate (Ag3PO4) has high quantum efficiency and photocatalytic degradation activity. However, Ag3PO4 is prone to photoelectron corrosion and becomes unstable during photocatalysis, which severely limits its application in this field. In this study, a tubelike g-C3N4/Ag3PO4 heterojunction was constructed by the chemical precipitation method. An Ag3PO4 nanoparticle was loaded onto the surface of the tubelike g-C3N4, forming close contact. The photocatalytic activity of the photocatalyst was evaluated by the degradation of RhB under visible-light irradiation. The tubelike g-C3N4/Ag3PO4-5% heterojunction exhibited optimal photocatalytic performance. In an optimal process, the degradation rate of the RhB is 90% under visible-light irradiation for 40 min. The recycling experiment showed that there was no apparent decrease in the activity of tubelike g-C3N4/Ag3PO4-5% heterojunction after five consecutive runs. A possible Z-type mechanism is proposed to explain the high activity and stability of the heterojunction.
10
Subramanian, Yathavan, Anitha Dhanasekaran, Lukman Ahmed Omeiza, Mahendra Rao Somalu, and Abul K. Azad. "A Review on Heteroanionic-Based Materials for Photocatalysis Applications." Catalysts 13, no. 1 (January 11, 2023): 173. http://dx.doi.org/10.3390/catal13010173.
Full textAbstract:
In the last few decades, photocatalysis has been found to be a practical, environmentally friendly approach for degrading various pollutants into non-toxic products (e.g., H2O and CO2) and generating fuels from water using solar light. Mainly, traditional photocatalysts (such as metal oxides, sulfides, and nitrides) have shown a promising role in various photocatalysis reactions. However, it faces many bottlenecks, such as a wider band gap, low light absorption nature, photo-corrosion issues, and quick recombination rates. Due to these, a big question arises of whether these traditional photocatalysts can meet increasing energy demand and degrade emerging pollutants in the future. Currently, researchers view heteroanionic materials as a feasible alternative to conventional photocatalysts for future energy generation and water purification techniques due to their superior light absorption capacity, narrower band gap, and improved photo-corrosion resistance. Therefore, this article summarizes the recent developments in heteroanionic materials, their classifications based on anionic presence, their synthesis techniques, and their role in photocatalysis. In the end, we present a few recommendations for improving the photocatalytic performance of future heteroanionic materials.
11
Mills, Andrew, Richard H. Davies, and David Worsley. "Water purification by semiconductor photocatalysis." Chemical Society Reviews 22, no. 6 (1993): 417. http://dx.doi.org/10.1039/cs9932200417.
Full text
12
Ren, Qiang, Juming Liu, Qi Yang, and Wei Shen. "A Review: Photocatalysts Based on BiOCl and g-C3N4 for Water Purification." Catalysts 11, no. 9 (September 8, 2021): 1084. http://dx.doi.org/10.3390/catal11091084.
Full textAbstract:
Many organic pollutants are discharged into the environment, which results in the frequent detection of organic pollutants in surface water and underground water. Some of the organic pollutants can stay for a long time in the environment due to their recalcitrance. Advanced oxidation processes (AOPs) can effectively treat the recalcitrant organic compounds in water. Photocatalysis as one of the AOPs has attracted a lot of interest. BiOCl and g-C3N4 are nice photocatalysts. However, their catalytic activity should be further improved for industrial utilization. The construction of heterojunction between the two different components is deemed as an efficient strategy for developing a highly efficient photocatalyst. As a typical type-II heterojunction, g-C3N4/BiOCl heterojunctions showed better photocatalytic performance. To date, the g-C3N4/BiOCl composites were mainly studied in the field of water purification. The photoactivity of the pristine catalysts was greatly enhanced by the combination of the two materials. However, three kinds of proposed mechanisms were used to explain the improvement of the g-C3N4/BiOCl heterojunctions. But few researchers tried to explain why there were three different scenarios employed to explain the charge transfer. According to the articles reviewed, no direct evidence could indicate whether the band structures of the heterojunctions based on BiOCl and g-C3N4 were changed. Therefore, many more studies are needed to reveal the truth. Having a clearer understanding of the mechanism is beneficial for researchers to construct more efficient photocatalysts. This article is trying to start a new direction of research to inspire more researchers to prepare highly effective photocatalysts.
13
Xu, Shengnan, Gang Xiao, Zishuai Wang, Yaoqiang Wang, Ziwei Liu, and Haijia Su. "A reusable chitosan/TiO2@g-C3N4 nanocomposite membrane for photocatalytic removal of multiple toxic water pollutants under visible light." Water Science and Technology 83, no. 12 (May 13, 2021): 3063–74. http://dx.doi.org/10.2166/wst.2021.188.
Full textAbstract:
Abstract Photocatalysis has been proved to be a promising approach in wastewater purification. However, it is hard to recycle powdery photocatalysts from wastewater in industry, but immobilizing them using larger materials can overcome this drawback. For that reason, TiO2@g-C3N4 was embedded into chitosan to synthesize a highly reusable and visible-light-driven chitosan/TiO2@g-C3N4 nanocomposite membrane (CTGM). CTGM showed enhanced photoactivity and the photocatalytic efficiencies of the toxic water pollutants methyl orange (M.O.), rhodamine B (Rh.B), chromium (VI) (Cr (VI)), 2,4-dichlorophenol (2,4-DCP) and atrazine (ATZ) were more than 90% under visible light at ambient conditions. Significantly, CTGM was easy to recycle and showed excellent reusability: there was no decrease in the photocatalytic decolorization efficiency of Rh.B throughout 10 cycles. A continuous-flow photocatalysis system was set up and 90% of Rh.B was effectively decolorized. A simple approach was developed to prepare a novel, effective and visible-light-driven membrane that was easy to reuse, and a feasible photocatalysis continuous-flow system was designed to be a reference for wastewater treatment in industry.
14
Kumar, Rajeev, Md Abu Taleb, Mohamed A. Barakat, and Bandar Al-Mur. "Design of BiOCl/WO3@Polyaniline Organic–Inorganic Nanocomposite Photocatalyst for the Efficient Decontamination of 2-Chlorophenol from Wastewater." Catalysts 13, no. 1 (January 11, 2023): 175. http://dx.doi.org/10.3390/catal13010175.
Full textAbstract:
Advanced photocatalysts that can utilize solar energy for water purification applications are always needed. The present article reports a facile fabrication of tungsten oxide (WO3)/bismuth oxychloride (BiOCl) immobilized on polyaniline (PAn) (BiOCl/WO3@PAn) heterojunction nanocomposite photocatalyst. The designed nanocatalyst was tested for 2-chlorophenol (2-CP) decontamination from the aquatic system. Synthesized WO3, BiOCl, and BiOCl/WO3@PAn nanocomposites were distinguished via UV-DSR, photoluminescence, SEM, TEM, XRD, and XPS analysis. The combination of PAn with WO3 and BiOCl showed a synergistic impact on the photocatalytic efficiency of the BiOCl/WO3@PAn nanocomposite. The synthesized BiOCl/WO3@PAn nanocomposite showed higher visible light absorption behavior and bandgap energy reduction than the WO3 and BiOCl. The obtained data shows that 2-CP photocatalysis by the BiOCl/WO3@PAn is controlled by degradation time, pH, and pollutant amount in the solution. The highest photocatalytic degradation of 2-CP (99.7%) was recorded at pH 5 and 25 mg/L concentration within 240 min. The photocatalysis mechanism and active radical scavenging study discovered that •O2− and •OH, were responsible for the 2-CP mineralization onto the BiOCl/WO3@PAn nanocomposite. The BiOCl/WO3@PAn nanocomposite showed enhanced decontamination properties over pristine catalysts. The reusability of the synthesized BiOCl/WO3@PAn nanocomposite was evaluated. It found that the photocatalyst could be recycled for up to four cycles for 2-CP degradation without significantly losing the photocatalytic properties. The fabricated BiOCl/WO3@PAn nanocomposite catalyst presented exceptional catalytic and recycling properties, indicating an effective method for scavenging hazardous organic contaminants under solar irradiation and green technology for wastewater purification.
15
Omar, Y., M. Chafaa, M. A. Bezzerrouk, M. Maatoug, M. F. Hachemi, and M. Kharitonov. "Application of the photocatalysis for the water purification and forthcoming irrigation." Ukrainian Journal of Ecology 7, no. 4 (December 30, 2017): 682–88. http://dx.doi.org/10.15421/2017_180.
Full textAbstract:
The considerable development of agricultural and industrial activity, has led to the emergence of new classes of organic pollutants say "persistent" which are resistant to the processes of conventional treatment of the waters. The photocatalysis represents of our days, emerging solution to the problems of pollution of groundwater environments, because that can degrade organic matter in basic products and less toxic. This technique associated with a biological method "bio-monitoring" allows to purify the waters effectively, simple and less costly. The use of photocatalytic process in the presence of photocatalyst SnO2 and Lemna minor under UV light has revealed a decrease in the absorbance by report to the initial state and that the rate of absorption varies from 7% to 33% for wastewater and 7% to 34% for the waters of the dam Dahmouni. The treatment of the waters by photocatalysis associated with the lenses of water could be a reality in the countries with strong sunlight to here to a dozen years. This technique is interesting both from the point of view of technology that from the environmental point of view. In effect, this technique may be extended to large scale for addressing releases industrial or domestic or for the purification of contaminated waters.Two water resourses including the dam Dahmounie and wastewater treatment plant in the city of Tiaret are in in the focus of this study.
16
Zouzelka, Radek, Jiri Olejnicek, Petra Ksirova, Zdenek Hubicka, Jan Duchon, Ivana Martiniakova, Barbora Muzikova, et al. "Hierarchical TiO2 Layers Prepared by Plasma Jets." Nanomaterials 11, no. 12 (November 30, 2021): 3254. http://dx.doi.org/10.3390/nano11123254.
Full textAbstract:
Heterogeneous photocatalysis of TiO2 is one of the most efficient advanced oxidation processes for water and air purification. Here, we prepared hierarchical TiO2 layers (Spikelets) by hollow-cathode discharge sputtering and tested their photocatalytic performance in the abatement of inorganic (NO, NO2) and organic (4-chlorophenol) pollutant dispersed in air and water, respectively. The structural-textural properties of the photocatalysts were determined via variety of physico-chemical techniques (XRD, Raman spectroscopy, SEM, FE-SEM. DF-TEM, EDAX and DC measurements). The photocatalysis was carried out under conditions similar to real environment conditions. Although the abatement of NO and NO2 was comparable with that of industrial benchmark Aeroxide® TiO2 P25, the formation of harmful nitrous acid (HONO) product on the Spikelet TiO2 layers was suppressed. Similarly, in the decontamination of water by organics, the mineralization of 4-chlorophenol on Spikelet layers was interestingly the same, although their reaction rate constant was three-times lower. The possible explanation may be the more than half-magnitude order higher external quantum efficacy (EQE) compared to that of the reference TiO2 P25 layer. Therefore, such favorable kinetics and reaction selectivity, together with feasible scale-up, make the hierarchical TiO2 layers very promising photocatalyst which can be used for environmental remediation.
17
Gao, Ting, Ke Zhang, Qiuhui Zhu, Qingyun Tian, Hui Wang, Wei Zhang, Jiangyushan Liang, et al. "One Step Synthesis of Oxygen Defective Bi@Ba2TiO4/BaBi4Ti4O15 Microsheet with Efficient Photocatalytic Activity for NO Removal." Catalysts 12, no. 11 (November 17, 2022): 1455. http://dx.doi.org/10.3390/catal12111455.
Full textAbstract:
Photocatalysis is an effective technology for NO removal even at low concentrations in the ambient atmosphere. However, the low efficiency of this advanced process and the tendency of producing toxic byproducts hinder the practical application of photocatalysis. To overcome these problems, the Bi@Ba2TiO4/BaBi4Ti4O15 photocatalytic composites were successfully prepared by a one-step hydrothermal method. The as-synthesized photocatalysts exhibited an efficient photocatalytic performance and generated low amounts of toxic byproducts. X-ray diffraction studies show that Bi3+ is successfully reduced on the surface of Ba2TiO4/BaBi4Ti4O15 (BT/BBT). After L-Ascorbic acid (AA) modification, the photocatalytic NO removal efficiency of Bi@Ba2TiO4/BaBi4Ti4O15 is increased from 25.55% to 67.88%, while the production of the toxic byproduct NO2 is reduced by 92.02%, where the initial concentration of NO is diluted to ca. 800 ppb by the gas stream and the flow rate is controlled at 301.98 mL·min−1 in a 150 mL cylindrical reactor. Furthermore, ambient humidity has little effect on the photocatalytic performance of theBi@Ba2TiO4/BaBi4Ti4O15, and the photocatalyst exhibits excellent reusability after repeated cleaning with deionized water. The improved photocatalytic effect is attributed to the addition of AA in BT/BBT being able to reduce Bi3+ ions to form Bi nanoparticles giving surface plasmon effect (SPR) and generate oxygen vacancies (OVs) at the same time, thereby improving the separation efficiency of photogenerated carriers, enhancing the light absorption, and increasing the specific surface areas. The present work could provide new insights into the design of high-performance photocatalysts and their potential applications in air purification, especially for NO removal.
18
Gao, Lan, Elyes Nefzaoui, Frédéric Marty, Mazen Erfan, Stéphane Bastide, Yamin Leprince-Wang, and Tarik Bourouina. "TiO2-Coated ZnO Nanowire Arrays: A Photocatalyst with Enhanced Chemical Corrosion Resistance." Catalysts 11, no. 11 (October 27, 2021): 1289. http://dx.doi.org/10.3390/catal11111289.
Full textAbstract:
Photocatalysis is proven to be the most efficient and environmentally friendly method for the degradation of organic pollutants in water purification. To meet the requirement of large-scale water treatment, there are two important points: One is the lifetime and chemical stability of the photocatalyst material, especially in the complex and harsh aqueous conditions. The other is the ease of synthesis of such photocatalysts with specific nano-morphology. In this work, two common photocatalyst materials, zinc oxide (ZnO) and titanium dioxide (TiO2), are selected to form more sustainable photocatalysts with high chemical stability. This involves the combination of both TiO2 and ZnO in a two-step simple synthesis method. It appears advantageous to exploit the conformal deposition of atomic layer deposition (ALD) to achieve nanometer-thick TiO2 coating on ZnO nanowires (NWs) with a high aspect ratio, which are firmly anchored to a substrate and exhibit a large specific surface area. The high chemical stability of the ALD TiO2 coating has been investigated in detail and proven to be effective under both strong acid and strong alkaline aqueous solutions. In addition, photocatalysis experiments with organic dyes show that via this simple two-step synthesis method, the produced ZnO/TiO2 tandem photocatalysts does indeed exhibit improved chemical stability in a harsh environment, while allowing efficient photodegradation.
19
Bak, Tadeusz, Truls Norby, Janusz Nowotny, Maria K. Nowotny, and Nikolaus Sucher. "Titanium Dioxide Photocatalyst - Unresolved Problems." Solid State Phenomena 162 (June 2010): 77–90. http://dx.doi.org/10.4028/www.scientific.net/ssp.162.77.
Full textAbstract:
The present work considers the performance of TiO2-based photosensitive oxide semiconductors as photocatalysts for water purification. This paper brings together the concepts of solid state chemistry for nonstoichiometric compounds and the concepts of photocatalysis in order to discuss the reactivity between TiO2 and water including microorganisms (bacteria and viruses). The performance of TiO2 photocatalysts are considered in terms of a model of photoelectrochemical cell. The experimental data on photocatalytic removal of microorganisms from water are considered in terms of the effect of several properties, including pH, dispersion, light intensity, and temperature. It is argued that correct understanding of the performance of TiO2 photocatalysts requires recognition that properties of TiO2, which is a nonstoichiometric compound, are determined by defect disorder and the related ability to donate or accept electrons. The photocatalytic properties of TiO2 are considered in terms of the reactivity of both anodic and cathodic sites with water and the related charge transfer at the TiO2/H2O interface. It is shown that the formation of well defined photocatalysts requires knowledge of mass and charge transfer during processing and performance, respectively. The main hurdles in the development of high-performance photocatalysts are discussed.
20
Wang, Ning, Xuming Zhang, Yu Wang, Weixing Yu, and Helen L. W. Chan. "Microfluidic reactors for photocatalytic water purification." Lab Chip 14, no. 6 (2014): 1074–82. http://dx.doi.org/10.1039/c3lc51233a.
Full text
21
Belessiotis, George V., Pinelopi P. Falara, Islam Ibrahim, and Athanassios G. Kontos. "Magnetic Metal Oxide-Based Photocatalysts with Integrated Silver for Water Treatment." Materials 15, no. 13 (July 1, 2022): 4629. http://dx.doi.org/10.3390/ma15134629.
Full textAbstract:
In this review, the most recent advances in the field of magnetic composite photocatalysts with integrated plasmonic silver (Ag) is presented, with an overview of their synthesis techniques, properties and photocatalytic pollutant removal applications. Magnetic attributes combined with plasmonic properties in these composites result in enhancements for light absorption, charge-pair generation-separation-transfer and photocatalytic efficiency with the additional advantage of their facile magnetic separation from water solutions after treatment, neutralizing the issue of silver’s inherent toxicity. A detailed overview of the currently utilized synthesis methods and techniques for the preparation of magnetic silver-integrated composites is presented. Furthermore, an extended critical review of the most recent pollutant removal applications of these composites via green photocatalysis technology is presented. From this survey, the potential of magnetic composites integrated with plasmonic metals is highlighted for light-induced water treatment and purification. Highlights: (1) Perspective of magnetic properties combined with plasmon metal attributes; (2) Overview of recent methods for magnetic silver-integrated composite synthesis; (3) Critical view of recent applications for photocatalytic pollutant removal.
22
Vidal, Alfonso. "Developments in solar photocatalysis for water purification." Chemosphere 36, no. 12 (May 1998): 2593–606. http://dx.doi.org/10.1016/s0045-6535(97)10221-1.
Full text
23
MILLS, A., R. H. DAVIES, and D. WORSLEY. "ChemInform Abstract: Water Purification by Semiconductor Photocatalysis." ChemInform 25, no. 12 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199412335.
Full text
24
Kumar, Jatinder, and Ajay Bansal. "Photocatalysis by Nanoparticles of Titanium Dioxide for Drinking Water Purification: A Conceptual and State-of-Art Review." Materials Science Forum 764 (July 2013): 130–50. http://dx.doi.org/10.4028/www.scientific.net/msf.764.130.
Full textAbstract:
To overcome the water pollution problems, and to meet stringent environmental regulations, scientist and researchers have been focusing on the development of new water purification processes. One such group of new technologies is advanced oxidation processes (AOPs). Among the AOPs, titanium dioxide photocatalysis has been widely studied on lab scale by the researchers for decontamination of drinking water. In the present chapter, a conceptual as well as state-of-art review of titanium dioxide photocatalysis for water purification has been discussed.
25
Feliczak-Guzik, Agnieszka. "Nanomaterials as Photocatalysts—Synthesis and Their Potential Applications." Materials 16, no. 1 (December 25, 2022): 193. http://dx.doi.org/10.3390/ma16010193.
Full textAbstract:
Increasing demand for energy and environmental degradation are the most serious problems facing the man. An interesting issue that can contribute to solving these problems is the use of photocatalysis. According to literature, solar energy in the presence of a photocatalyst can effectively (i) be converted into electricity/fuel, (ii) break down chemical and microbial pollutants, and (iii) help water purification. Therefore, the search for new, efficient, and stable photocatalysts with high application potential is a point of great interest. The photocatalysts must be characterized by the ability to absorb radiation from a wide spectral range of light, the appropriate position of the semiconductor energy bands in relation to the redox reaction potentials, and the long diffusion path of charge carriers, besides the thermodynamic, electrochemical, and photoelectrochemical stabilities. Meeting these requirements by semiconductors is very difficult. Therefore, efforts are being made to increase the efficiency of photo processes by changing the electron structure, surface morphology, and crystal structure of semiconductors. This paper reviews the recent literature covering the synthesis and application of nanomaterials in photocatalysis.
26
Michalec, Kinga, and Anna Kusior. "From Adsorbent to Photocatalyst: The Sensitization Effect of SnO2 Surface towards Dye Photodecomposition." Molecules 26, no. 23 (November 25, 2021): 7123. http://dx.doi.org/10.3390/molecules26237123.
Full textAbstract:
Semiconductor photocatalysis is considered one of the most promising technologies for water purification from toxic organic dyes. However, to reliably evaluate the possibility of using a given material as a photocatalyst, it is crucial to investigate not only the photocatalytic activity but also its affinity towards various dyes and reusability. In this work, we studied the adsorptive/photocatalytic properties of hollow-spherical raspberry-like SnO2 and its SnO2/SnS2 heterostructures that were obtained via a chemical conversion method using three different concentrations of a sulfide precursor (thioacetamide). The adsorptive/photocatalytic properties of the samples towards cationic rhodamine B (RhB) and anionic indigo carmine (IC) were analyzed using uncommon wall zeta potential measurements, hydrodynamic diameter studies, and adsorption/photodecomposition tests. Moreover, after conducting cyclic experiments, we investigated the (micro)structural changes of the reused photocatalysts by scanning electron microscopy and Fourier-transform infrared spectroscopy. The obtained results revealed that the sensitization of SnO2 resulted not only in the significantly enhanced photocatalytic performance of the heterostructures, but also completely changed their affinity towards dyes. Furthermore, despite the seemingly best photocatalytic performance, the sample with the highest SnS2 content was unstable due to its (micro)structure. This work demonstrates that dye adsorption/desorption processes may overlap the results of cyclic photodecomposition kinetics.
27
Chaturvedi, Shalini, and Pragnesh N. Dave. "Environmental Application of Photocatalysis." Materials Science Forum 734 (December 2012): 273–94. http://dx.doi.org/10.4028/www.scientific.net/msf.734.273.
Full textAbstract:
Recent interest and studies in environmental photo-chemistry, in natural photosynthesis, and chemical methods for solar energy transformations has contributed greatly to our knowledge and understanding of the various phenomena related to both photo-chemistry and catalysis. As an emerging nanotechnology come together with the chemical mechanisms of photo-catalysis, the photo-catalytic nanoparticle titanium dioxide offers a new meaning of remediation and degradation on volatile organic compounds in the aqueous and airs streams. In this chapter we discuss about application of photocatalysis in environment like biological contamination, air purification, water disinfection, hazardous waste remediation, water purification, self-clean buildings, deodorizing, anti-bacterial action, anti-fogging resolving cleaning action etc.
28
Xu, Difa, Shaowen Cao, Jinfeng Zhang, Bei Cheng, and Jiaguo Yu. "Effects of the preparation method on the structure and the visible-light photocatalytic activity of Ag2CrO4." Beilstein Journal of Nanotechnology 5 (May 19, 2014): 658–66. http://dx.doi.org/10.3762/bjnano.5.77.
Full textAbstract:
Silver chromate (Ag2CrO4) photocatalysts are prepared by microemulsion, precipitation, and hydrothermal methods, in order to investigate the effect of preparation methods on the structure and the visible-light photocatalytic activity. It is found that the photocatalytic activity of the prepared Ag2CrO4was highly dependent on the preparation methods. The sample prepared by microemulsion method exhibits the highest photocatalytic efficiency on the degradation of methylene blue (MB) under visible-light irradiation. The enhanced photocatalytic activity could be ascribed to the smaller particle size, higher surface area, relatively stronger light absorption, and blue-shift absorption edge, which result in the adsorption of more MB molecules, a shorter diffusion process of more photogenerated excitons, and a stronger oxidation ability of the photogenerated holes. Considering the universalities of microemulsion, precipitation, and hydrothermal methods, this work may also provide a prototype for the comparative study of semiconductor based photocatalysis for water purification and environmental remediation.
29
Martin, David James, Guigao Liu, Savio J. A. Moniz, Yingpu Bi, Andrew M. Beale, Jinhua Ye, and Junwang Tang. "Efficient visible driven photocatalyst, silver phosphate: performance, understanding and perspective." Chemical Society Reviews 44, no. 21 (2015): 7808–28. http://dx.doi.org/10.1039/c5cs00380f.
Full text
30
Tian, Yankuan, Xin Yang, Long Xu, Xueli Wang, Jianyong Yu, Dequn Wu, Faxue Li, and Tingting Gao. "A Composite Fabric with Dual Functions for High-Performance Water Purification." Materials 15, no. 17 (August 26, 2022): 5917. http://dx.doi.org/10.3390/ma15175917.
Full textAbstract:
The dilemma of diminishing freshwater resources caused by water pollution has always impacted human life. Solar-driven interfacial evaporation technology has the potential for freshwater production via solar-driven distillation. However, in solar-driven interfacial evaporation technology, it is difficult to overcome the problem of wastewater containing various contaminants. In this work, we propose a bifunctional fabric created by depositing titanium dioxide@carbon black nanoparticles onto cotton fabric (TiO2@CB/CF). The TiO2@CB/CF has a coupling effect that includes the photothermal effect of CB and photocatalysis of TiO2, and it can not only generate clean water but can also purify contaminated water. The resulting bifunctional fabric can achieve an outstanding water evaporation rate of 1.42 kg m−2 h−1 and a conversion efficiency of 90.4% in methylene blue (MB) solution under one-sun irradiation. Simultaneously, the TiO2@CB/CF demonstrates a high photocatalytic degradation of 57% for MB solution after 2 h with light irradiation. It still shows a good photocatalysis effect, even when reused in an MB solution for eight cycles. Furthermore, the TiO2@CB/CF delivers excellent performance for actual industrial textile dyeing wastewater. This bifunctional fabric has a good application prospect and will provide a novel way to resolve the issue of freshwater scarcity.
31
Zhu, Bolin, Xuefei Li, Yue Wang, Na Liu, Ye Tian, and Jinghai Yang. "Visible-light-driven photocatalytic degradation of RhB by carbon-quantum-dot-modified g-C3N4 on carbon cloth." CrystEngComm 23, no. 27 (2021): 4782–90. http://dx.doi.org/10.1039/d1ce00396h.
Full text
32
Roysen, A., and T. Musienko. "Photocatalytic water purification from dioxins (fragments of theory)." National Security and Strategic Planning 2020, no. 3 (September 30, 2020): 111–20. http://dx.doi.org/10.37468/2307-1400-2020-3-111-120.
Full textAbstract:
Contamination of all natural sources of drinking water by human activities has become a matter of extreme concern to all who understand this problem as a threat to civilization. Dioxins and dioxin-like substances have been classified as particularly dangerous pollutants in the last thirty years. The authors provide generalized information about the danger of environmental pollution with dioxins and dioxin-like toxicants. It is suggested that the total weakening of the immunity of the world's population due to the presence of dioxins in the environment, which are hormone-like superecotoxicants. The factor of mass exposure of the population to coronavirus infection (COVID 19) is not excluded, as a result of the impact of dioxins and dioxin-like substances on the human immune system. The authors consider the most promising method of drinking water purification to be the photocatalysis method implemented directly in a local source (domestic consumption, production of bottled water). The physicochemical process of photocatalytic water purification using TiO2 activated by artificial ultraviolet radiation as a catalyst is considered. It is reported about the work aimed at the practical implementation of measures for the purification of drinking water.
33
Ivantsova, Natalya A., Evgeniy N. Kuzin, and Alina A. Churina. "Photocatalytic water purification from phenol and formaldehyde." Izvestiya of Saratov University. Chemistry. Biology. Ecology 22, no. 3 (September 22, 2022): 275–81. http://dx.doi.org/10.18500/1816-9775-2022-22-3-275-281.
Full textAbstract:
Industrial development leads to an increasing number of persistent and highly toxic organic compounds such as phenol and formaldehyde. Chemical oxidation processes (in particular, photooxidation) are widely used for water treatment and wastewater and groundwater treatment. As part of the work done, an assessment of the possibility of using photocatalysis for post-treatment of wastewater from phenol, formaldehyde, and their mixtures has been carried out. The processes of photooxidation of formaldehyde, phenol and their mixtures in an aqueous medium under the individual and combined effects of ultraviolet radiation and titanyl sulfate have been studied. The high efficiency (up to 90%) of photocatalytic post-treatment of wastewater containing phenol and formaldehyde has been determined. It has been established that ultraviolet water treatment under static conditions can significantly reduce the concentrations of phenol and formaldehyde to the values of the discharge standard into the city water canal. It has been proven that the introduction of titanyl sulfate microadditives (homogeneous photocatalytic process) makes it possible to intensify the oxidation process, while the addition of titanium(IV) compounds, due to its chemical inertness, will not have a toxic effect on the activated sludge biocenosis. Possible intermediate products of photooxidative degradation of phenol and formaldehyde are qualitatively determined. The kinetic dependences of the oxidation of phenol, formaldehyde and their mixtures are obtained, which allow further scaling up the process of photodegradation with the introduction of homogeneous catalysts for industrial facilities into the system. The proposed post-treatment method is included in the Best Available Techniques directory and will improve environmental and industrial safety.
34
Blanco, Miren, Cristina Monteserín, Adrián Angulo, Ana Pérez-Márquez, Jon Maudes, Nieves Murillo, Estíbaliz Aranzabe, Leire Ruiz-Rubio, and Jose Luis Vilas. "TiO2-Doped Electrospun Nanofibrous Membrane for Photocatalytic Water Treatment." Polymers 11, no. 5 (April 26, 2019): 747. http://dx.doi.org/10.3390/polym11050747.
Full textAbstract:
This work has been focused on the one-step fabrication by electrospinning of polyamide 6 (PA6) nanofibre membranes modified with titanium dioxide nanoparticles (TiO2), where these TiO2 nanoparticles aggregates could induce a photocatalytic activity. The main potential application of these membranes could be the purification of contaminated water. Thus, it is important to analyse the contaminant degradation capability since in these membranes this is based on their photocatalytic activity. In this work, the effect of the photocatalysis has been studied both on the degradation of an organic model contaminant and on the removal of Escherichia coli and other coliform bacteria. As a result, it was observed that these membranes present excellent photocatalytic activity when they are irradiated under UV light, allowing a 70% reduction of an organic model pollutant after 240 min. In addition, these membranes successfully removed Escherichia coli and other coliform bacteria in artificially inoculated water after 24 h of contact with them. Moreover, the stand-alone structure of the membranes allowed for the reusing of the immobilized catalyst. The experimental evidence indicated that developed nanofibre membranes are a fast and efficient solution for polluted water decontamination based on photocatalysis. Their use could contribute to guarantee a fresh water level and quality, mitigating the water scarcity problem worldwide.
35
Pichat, Pierre. "A short overview of the state of the art and perspectives on the main basic factors hindering the development of photocatalytic treatment of water." Water Supply 15, no. 1 (August 21, 2014): 1–10. http://dx.doi.org/10.2166/ws.2014.083.
Full textAbstract:
This brief overview focuses on three of the main basic phenomena limiting the applications of photocatalysis using semiconductors for the treatment of water, so that this technology has really not gone beyond the demonstration stage aside from niche applications. These phenomena are: the recombination of photogenerated charges; the adsorption of trace organic pollutants; the spectral range of photocatalytic activity. The accomplishments and failures of the various and numerous attempts to overcome these fundamental limitations are summarized and discussed. The emphasis is on the methods susceptible to improve the use of photons, including those in the visible domain to better use solar irradiation if applicable, and to facilitate the contact between the semiconductor and the trace organic pollutants in liquid water. Despite numerous studies, these limitations have not yet been overcome for water purification, because additionally the photocatalysts must contain chemical elements that are both innocuous and inexpensive. However, combinations of TiO2 and activated carbon might provide materials of interest.
36
Tsymbal, D. O., and M. E. Mazanik. "Rationale for the use of photocatalysis for natural and drinking water purification from pollutants of biological origin." Health and Ecology Issues 18, no. 4 (December 31, 2021): 143–52. http://dx.doi.org/10.51523/2708-6011.2021-18-4-19.
Full textAbstract:
Objective. To evaluate the effectiveness of photocatalytic methods of oxidation of organic substances for the preparation of drinking water. To show the expediency of the use of the described method for the design of wastewater treatment facilities.Materials and methods. The oxidation degrees of 58 organic substances of various hazard classes were studied. The sampling frame was based on two characteristics: origin (biological and artificial) and the oxidation state stated in different sources.Results. A high efficiency of photocatalysis for the destruction of organic substances in wastewater from various industries has been shown: the degrees of oxidation range from 70 to 100 %.Conclusion. Photocatalysis can be used to design wastewater treatment facilities with a view to reducing the probability of biological pollution of natural waters intended for drinking water production.
37
Bahari, Shariena Shamsul, Yuen Mei Lian, Ros Azlinawati Ramli, and Lee Siew Ling. "Photodegradation of Reactive Blue 4 Using Suspension of Anatase-Titanium Dioxide and Corn Cob." Key Engineering Materials 932 (September 20, 2022): 45–58. http://dx.doi.org/10.4028/p-mt4a60.
Full textAbstract:
Textile dyeing often employs reactive dyes. The dye wastewater contains hazardous materials and is toxic to humans and the environment. Photodegradation using a semiconductor photocatalyst is a promising alternative approach for water purification and wastewater treatment. However, the photocatalyst’s low adsorption ability is a problem in the photocatalysis process. To compensate for this shortcoming, photocatalyst content must be combined with an adsorbent. Raw corn cob and titanium dioxide (TiO2) were used in this photocatalysis. Due to a synergistic impact, raw corn cob’s ability to adsorb and titanium dioxide’s ability to photodegrade organic pollutants from water bodies is expected to boost the removal performance. The degradation of Reactive Blue 4 (RB4) as a targeted dye was carried out in this research using a suspended mixture of commercial anatase TiO2 and raw corn cob under UV light. The effect of initial pH solution, initial dye concentration and contact time, TiO2-corn cob dosages, and the influence of other pollutants were investigated as factors influencing photodegradation-adsorption of RB4. The high removal rate of RB4 was obtained at a low pH of 2 and RB4 concentration of 40 ppm. The increased dose of TiO2-corn cob improved the RB4 dye removal performance. In conclusion, combining photodegradation and adsorption systems as a hybrid treatment method resulted in a synergistic increase in the efficiency of RB4 removal.
38
Tetteh, E. Kweinor, S. Rathilal, D. Asante-Sackey, and M. Noro Chollom. "Prospects of Synthesized Magnetic TiO2-Based Membranes for Wastewater Treatment: A Review." Materials 14, no. 13 (June 24, 2021): 3524. http://dx.doi.org/10.3390/ma14133524.
Full textAbstract:
Global accessibility to clean water has stressed the need to develop advanced technologies for the removal of toxic organic and inorganic pollutants and pathogens from wastewater to meet stringent discharge water quality limits. Conventionally, the high separation efficiencies, relative low costs, small footprint, and ease of operation associated with integrated photocatalytic-membrane (IPM) technologies are gaining an all-inclusive attention. Conversely, photocatalysis and membrane technologies face some degree of setbacks, which limit their worldwide application in wastewater settings for the treatment of emerging contaminants. Therefore, this review elucidated titanium dioxide (TiO2), based on its unique properties (low cost, non-toxicity, biocompatibility, and high chemical stability), to have great potential in engineering photocatalytic-based membranes for reclamation of wastewater for re-use. The environmental pathway of TiO2 nanoparticles, membranes and configuration types, modification process, characteristics, and applications of IPMs in water settings are discussed. Future research and prospects of magnetized TiO2-based membrane technology is highlighted as a viable water purification technology to mitigate fouling in the membrane process and photocatalyst recoverability. In addition, exploring life cycle assessment research would also aid in utilizing the concept and pressing for large-scale application of this technology.
39
Kanth, Namrata, Weiheng Xu, Umesh Prasad, Dharneedar Ravichandran, Arunachala Mada Kannan, and Kenan Song. "PMMA-TiO2 Fibers for the Photocatalytic Degradation of Water Pollutants." Nanomaterials 10, no. 7 (June 30, 2020): 1279. http://dx.doi.org/10.3390/nano10071279.
Full textAbstract:
Titanium dioxide (TiO2) is a promising photocatalyst that possesses a redox potential suitable for environmental remediation applications. A low photocatalytic yield and high cost have thus far limited the commercial adoption of TiO2-based fixed-bed reactors. One solution is to engineer the physical geometry or chemical composition of the substrate to overcome these limitations. In this work, porous polymethyl methacrylate (PMMA) substrates with immobilized TiO2 nanoparticles in fiber forms were fabricated and analyzed to demonstrate the influence of contaminant transport and light accessibility on the overall photocatalytic performance. The influences of (i) fiber porosity and (ii) fiber architecture on the overall photocatalytic performance were investigated. The porous structure was fabricated using wet phase inversion. The core-shell-structured fibers exhibited much higher mechanical properties than the porous fibers (7.52 GPa vs. non-testability) and maintained the same degradation rates as porous structures (0.059 vs. 0.053/min) in removing methylene blue with comparable specific surface areas. The highest methylene blue (MB) degradation rate (kMB) of 0.116 min−1 was observed due to increases of the exposed surface area, pointing to more efficient photocatalysis by optimizing core-shell dimensions. This research provides an easy-to-manufacture and cost-efficient method for producing PMMA/TiO2 core-shell fibers with a broad application in water treatment, air purification, and volatile sensors.
40
Wang, Jingwen, Takuya Hasegawa, Yusuke Asakura, and Shu Yin. "Recent Advances in Ternary Metal Oxides Modified by N Atom for Photocatalysis." Catalysts 12, no. 12 (December 2, 2022): 1568. http://dx.doi.org/10.3390/catal12121568.
Full textAbstract:
Ternary metal oxides (TMOs) with flexible band structures are of significant potential in the field of photocatalysis. The efficient utilization of renewable and green solar energy is of great importance to developing photocatalysts. To date, a wide range of TMOs systems has been developed as photocatalysts for water and air purification, but their practical applications in visible light-assisted chemical reactions are hindered mainly by its poor visible light absorption capacity. Introduction of N atoms into TMOs can narrow the band-gap energy to a lower value, enhance the absorption of visible light and suppress the recombination rate of photogenerated electrons and holes, thus improving the photocatalytic performance. This review summarizes the recent research on N-modified TMOs, including the influence of N doping amounts, N doping sites, and N-induced phase transformation. The introduced N greatly tuned the optical properties, electronic structure, and photocatalytic activity of the TMOs. The optimal N concentration and the influence of N doping sites are investigated. The substitutional N and interstitial N contributed differently to the band gap and electron transport. The introduced N can tune the vacancies in TMOs due to the charge compensation, which is vital for inducing different activity and selectivity. The topochemical ammonolysis process can convert TMOs to oxynitride with visible light absorption. By altering the band structures, these oxynitride materials showed enhanced photocatalytic activity. This review provides an overview of recent advances in N-doped TMOs and oxynitrides derived from TMOs as photocatalysts for environmental applications, as well as some relevant pointers for future burgeoning research development.
41
Fiorenza, Roberto, Marcello Condorelli, Luisa D’Urso, Giuseppe Compagnini, Marianna Bellardita, Leonardo Palmisano, and Salvatore Scirè. "Catalytic and Photothermo-catalytic Applications of TiO2-CoOx Composites." Journal of Photocatalysis 1, no. 1 (October 2, 2020): 3–15. http://dx.doi.org/10.2174/2665976x01666200219113505.
Full textAbstract:
Objective: The necessity to have green and sustainable industrial processes has promoted new technologies for air and water purification together with the research of new energy sources. In this contest, the TiO2-based photocatalysis can be considered a promising route for both environmental applications aIn this work, we have investigated the photocatalytic performance of TiO2-CoOx composites on both photooxidation and photoreduction reactions. Specifically, we have compared the performance of the composites in the thermo-catalytic, photo-catalytic and photothermal-catalytic oxidation of ethanol chosen as model volatile organic compound (VOC) and in the photocatalytic hydrogen production by simulated solar light from aqueous solution of ethanol.nd hydrogen production through water splitting. Background: The necessity to have green and sustainable industrial processes has promoted new technologies for air and water purification together with the research of new energy sources. In this contest, the TiO2-based photocatalysis can be considered a promising route for both environmental applications and hydrogen production through water splitting. Methods: The samples were prepared with a simple impregnation method, and were characterized by Scanning Electron (SEM) and Transmission Electron (TEM) microscopies, X-ray powder diffraction (XRD), N2 adsorption-desorption measurements, Temperature Programmed Reduction in hydrogen (H2- TPR) and X-ray Photoelectron (XPS), Raman, UV-Vis Diffuse Reflectance (UV-Vis DRS) and Photoluminescence (PL) spectroscopies. The catalytic and photocatalytic activity were carried out on pyrex reactors irradiated with a solar lamp and analyzing the reactions products through gas chromatography. Results: The presence and the amount of cobalt oxide were found crucial in determining the performance of the TiO2-based composites for both the catalytic and photocatalytic processes. In particular, the addition of 1 weight percent of CoOx led to the best performance in the photocatalytic processes, whereas a higher amount was beneficial in the thermo-catalytic tests. The multi-catalytic approach based on the synergistic effect of photocatalysis and thermocatalysis in the presence of the TiO2-1%CoOx sample allowed the temperature necessary to obtain 50% ethanol conversion and 50% yield in CO2 to be reduced by 40°C and 50°C, respectively. The same sample was also the best catalyst for photocatalytic solar H2 production. Conclusion: The presence of small amounts of cobalt oxide leads to an efficient composite with TiO2 facilitating the space charge separation and increasing the lifetime of the generated photoholes and electrons. The wide versatility of TiO2-CoOx catalysts both for photooxidation and photoreduction reactions motivates to further exploit the use of these systems in real solar-driven photocatalysis.
42
Xi, Yaofang, Cui Du, Ping Li, Xin Zhou, Chen Zhou, and Shengyang Yang. "Combination of Photothermal Conversion and Photocatalysis toward Water Purification." Industrial & Engineering Chemistry Research 61, no. 13 (March 24, 2022): 4579–87. http://dx.doi.org/10.1021/acs.iecr.2c00116.
Full text
43
Sawant, Sadhana A., Ajinkya Nene, Savita P. Somani, Shreeniwas K. Omanwar, and Prakash R. Somani. "Simultaneous Waste Water Purification via Photocatalysis and Seed Germination." Green and Sustainable Chemistry 03, no. 03 (2013): 129–33. http://dx.doi.org/10.4236/gsc.2013.33015.
Full text
44
Bognár, Szabolcs, Predrag Putnik, and Daniela Šojić Merkulov. "Sustainable Green Nanotechnologies for Innovative Purifications of Water: Synthesis of the Nanoparticles from Renewable Sources." Nanomaterials 12, no. 2 (January 14, 2022): 263. http://dx.doi.org/10.3390/nano12020263.
Full textAbstract:
Polluting the natural water resources is a serious global issue, which is confirmed by the fact that today at least 2 billion people consume water from contaminated sources. The conventional wastewater treatment methods cannot effectively remove the persistent pollutants (e.g., drugs, organic dyes, pesticides) from the aqueous environment. Heterogeneous photocatalysis is a promising and sustainable alternative for water remediation. It is based on the interaction between light irradiation and the semiconductors (e.g., TiO2, ZnO) as photocatalysts, but these compounds, unfortunately, have some disadvantages. Hence, great attention has been paid to the nanotechnology as a possible way of improvement. Nanomaterials have extraordinary properties; however, their conventional synthesis is often difficult and requires a significant amount of dangerous chemicals. This concise topical review gives recent updates and trends in development of sustainable and green pathways in the synthesis of nanomaterials, as well as in their application for water remediation. In our review we put emphasis on the eco-friendly, mostly plant extract-based materials. The importance of this topic, including this study as well, is proved by the growing number of publications since 2018. Due to the current serious environmental issues (e.g., global warming, shortage of pure and quality water), it is necessary for the traditional TiO2 and ZnO semiconductors to be replaced with the harmless, non-toxic, and more powerful nanocomposites as photocatalysts. Not only because of their higher efficiency as compared to the bulk semiconductors, but also because of the presence of biomolecules that can add up to the pollutant removal efficiency, which has been already confirmed in many researches. However, despite the fact that the application of heterogeneous photocatalysis together with green nanotechnology is absolutely the future in water purification, there are some challenges which have to be overcome. The exact effects of the biomolecules obtained from plants in the synthesis of nanoparticles, as well as in the photocatalytic processes, are not exactly known and require further investigation. Furthermore, heterogeneous photocatalysis is a well-known and commonly examined process; however, its practical use outside the laboratory is expensive and difficult. Thus, it has to be simplified and improved in order to be available for everyone. The aim of our review is to suggest and prove that using these bio-inspired compounds it is possible to reduce human footprint in the nature.
45
Ignat, Eugenia Corina, Doina Lutic, Gabriel Ababei, and Gabriela Carja. "Novel Heterostructures of Noble Plasmonic Metals/Ga-Substituted Hydrotalcite for Solar Light Driven Photocatalysis toward Water Purification." Catalysts 12, no. 11 (November 2, 2022): 1351. http://dx.doi.org/10.3390/catal12111351.
Full textAbstract:
Heterostructures formed by close conjunctions of plasmonic metal nanoparticles and non-plasmonic (2D) lamellar nanostructures are receiving extensive interest as solar-light-driven photocatalysts for environmental pollutant remediation. Herein, the conjunction of plasmonic Au or Ag and Ga-substituted hydrotalcite are obtained by exploiting the manifestation of the structural “memory effect” of Ga-substituted hydrotalcite in the aqueous solutions of Au(CH3COO)3 and Ag2SO4, respectively. The 2D layered matrix of MgGaAl plays a dual function; it is involved in the synthesis of the plasmonic metal nanoparticles, and further, is acting as a support. The compressive investigations using X-ray diffraction (XRD), UV-diffuse reflectance spectroscopy (UVDR), infrared spectroscopy (FT-IR), transmission electron microscopy (TEM/HRTEM), high-angle annular dark-field imaging/scanning transmittance electron microscopy (HAADF/STEM) and X-ray photoelectron spectroscopy (XPS) describe structural, composition and nano/micromorphology characteristics of the novel heterostructures, while UVDR analysis afforded to study the features of their plasmonic responses. Results reveal that the catalysts are formed by close conjunction of small nanoparticles of Au or Ag (with a mean size less than 20 nm) that are formed on the larger particles of MgGaAl and own plasmonic features within the visible range. The catalysts performances were tested towards photocatalytic degradation of p-dichlorobenzene and 4-nitrophenol under solar light irradiation. Results revealed that the degradation of the pollutants is entangled to the plasmonic response of the heterostructured catalysts that is the key functionality in promoting photocatalysis and degrading the pollutants, under solar light irradiation. MgGaAl showed a very low photocatalytic activity when irradiated by UV or solar light. Notably, the heterostructured catalysts proceeded in good to excellent yield to remove the tested pollutants, under solar light irradiation. The sustainability of the novel catalysts was assessed through the kinetic analysis of the degradation processes of the tested pollutants and their mixture.
46
Tao, Yuhan. "Advanced Oxidation Processes for Water Purification Applications." International Journal of Innovation and Entrepreneurship 1, no. 1 (December 8, 2022): 1. http://dx.doi.org/10.56502/ijie1010002.
Full textAbstract:
The contamination of water resources has become a significant challenge that threatens the health and well-being of people’s daily life; it calls for new technologies to be applied for water purification. Heterogeneous Fenton or Fenton-like techniques have a lot of potential as a new approach for treating wastewater because of the advantages in efficiency, safety, and economics. Various advanced oxidation processes (AOPs) are comprehensively reviewed in this work, and the •OH generation methods including chemical, electro-chemical, and photochemical approaches are summarized. Some key parameters that influence the reaction efficiency such as the temperature, catalysts, H2O2 dosage, and pH are investigated. The reaction mechanism and process optimization of photocatalysis are specifically highlighted.
47
Qutub, Nida, Preeti Singh, Suhail Sabir, Khalid Umar, Suresh Sagadevan, and Won-Chun Oh. "Synthesis of Polyaniline Supported CdS/CdS-ZnS/CdS-TiO2 Nanocomposite for Efficient Photocatalytic Applications." Nanomaterials 12, no. 8 (April 14, 2022): 1355. http://dx.doi.org/10.3390/nano12081355.
Full textAbstract:
Photocatalytic degradation can be increased by improving photo-generated electrons and broadening the region of light absorption through conductive polymers. In that view, we have synthesized Polyaniline (PANI) with CdS, CdS-ZnS, and CdS-TiO2 nanocomposites using the chemical precipitation method, characterized and verified for the photo-degradation of Acid blue-29 dye. This paper provides a methodical conception about in what way conductive polymers “PANI” enhances the performance rate of composite photocatalysts (CdS, CdS-ZnS and CdS-TiO2). The nanocomposites charge transfer, molar ratio, surface morphology, particle size, diffraction pattern, thermal stability, optical and recombination of photo-generated charge carrier properties were determined. The production of nanocomposites and their efficient photocatalytic capabilities were observed. The mechanism of photocatalysis involved with PC, CZP and CTP nanocomposites are well presented by suitable diagrams representing the exchange of electrons and protons among themselves with supported equations. We discovered that increasing the number of nanocomposites in the membranes boosted both photocatalytic activity and degradation rate. CdS-Zinc-PANI (CZP) and CdS-TiO2-PANI(CTP) nanocomposites show entrapment at the surface defects of Zinc and TiO2 nanoparticles due to the demolition of unfavorable electron kinetics, and by reducing the charge recombination, greater photocatalytic activity than CdS-PANI (CP) with the same nanoparticle loading was achieved. With repeated use, the photocatalysts’ efficiency dropped very little, hinting that they may be used to remove organic pollutants from water. The photocatalytic activity of CZP and CTP photocatalytic membranes was greater when compared to CdS-PANI, which may be due to the good compatibility between CdS and Zinc and TiO2, as well efficient charge carrier separation. PANI can also increase the split-up of photo-excited charge carriers and extend the absorption zone when combined with these nanoparticles. As a result, the development of outrageous performance photocatalysts and their potential uses in ecological purification and solar power conversion has been facilitated. The novelty of this article is to present the degradation of AB-29 Dye using nanocomposites with polymers and study the enhanced degradation rate. Few studies have been carried out on polymer nanocomposites and their application in the degradation of AB-29 dyes and remediation of water purposes. Nanoparticle CdS is a very effective photocatalyst, commonly used for water purification along with nanoparticle ZnS and TiO2; but cadmium ion-leaching makes it ineffective for practical and commercial use. In the present work, we have reduced the leaching of hazardous cadmium ions by trapping them in a polyaniline matrix, hence making it suitable for commercial use. We have embedded ZnS and TiO2 along with CdS in a polyaniline matrix and compared their photocatalytic activity, stability, and reusability, proving our nano-composites suitable for commercial purposes with enhanced activities and stabilities, which is a novelty. All synthesized nanocomposites are active within the near-ultraviolet to deep infrared (i.e., 340–850 nm). This gives us full efficiency of the photocatalysts in the sunlight and further proves the commercial utility of our nanocomposites.
48
Umar, M., Nasir Mahmood, Saif Ullah Awan, Sabeen Fatima, Asif Mahmood, and Syed Rizwan. "Rationally designed La and Se co-doped bismuth ferrites with controlled bandgap for visible light photocatalysis." RSC Advances 9, no. 30 (2019): 17148–56. http://dx.doi.org/10.1039/c9ra03064f.
Full text
49
Hossain, S. M. Azad, Md Eaqub Ali, and Sharifah Bee Abd Hamid. "Synergizing TiO2 Surface to Enhance Photocatalysis: A Green Technology for Clean and Safe Environment - A Review." Advanced Materials Research 1109 (June 2015): 300–303. http://dx.doi.org/10.4028/www.scientific.net/amr.1109.300.
Full textAbstract:
Photocatalytic removal of pollutants from air and water is a green technology that helps us to maintain a healthy life, clean environment and a balanced ecosystem. Photo-excited TiO2has strong oxidation ability that can be used to purify indoor air and polluted water. Numerous parameters such as UV light intensity, humidity, substrate concentration, substrate type and O2partial pressure influence the removal rate of gaseous and/or aqueous contaminants. However, TiO2photocatalyst cannot decompose large amount of contaminants or refractory chemicals because of the interference in light penetration by the bulk pollutants. Modification of TiO2surface or combining the TiO2photocatalyst with other advanced oxidation processes such as sonolysis, ozonization, electrochemical oxidation and photocatalysis could significantly improve the photocatalytic efficiency of TiO2photocatalyst. This brief review is an up-to-date presentation of the TiO2surface modification for enhancing its photocatalytic activities for environmental purification.
50
Li, Dong Dong, Yan Hua Lei, Ning Tan, Tao Liu, Xue Ting Chang, Run Hua Fan, and Guan Hui Gao. "One-Step Hydrothermal Synthesis of 1T@2H MoS2 for Enhanced Photocatalytic Degradation Performance of Methyl Blue." Materials Science Forum 993 (May 2020): 1496–501. http://dx.doi.org/10.4028/www.scientific.net/msf.993.1496.
Full textAbstract:
Photocatalytic technology is widely used in water purification because of its environmental protection, high efficiency and energy saving. Therefore, it is extremely important for the selection and preparation of specific semiconductor materials used in the field of photocatalysis. In this work, 1T@2H MoS2 nanosheets were fabricated by simple hydrothermal method, and the photocatalytic property of as-prepared 1T@2H MoS2 were investigated by the photo-degradation of methylene blue (MB) water solutions under visible light irradiation via 2H MoS2.The results indicated that compared to 2H MoS2, the 1T@2H MoS2 exhibited more excellent photocatalytic degradation property. After 150 minutes of irradiation under visible light, 1T@2H MoS2 had a removal rate of 98% for MB, and 2H MoS2 eventually reached 19%. The enhancement photocatalytic property of 1T@2H MoS2 could be attributed to the reduced band gap energy of the hybrid-nanosheets and the increased in electron migration speed.