Journal articles: 'Carbon dopin'

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López-Salas, Nieves, María C. Gutiérrez, Conchi O. Ania, José Luís G. Fierro, M. Luisa Ferrer, and Francisco del Monte. "Efficient nitrogen-doping and structural control of hierarchical carbons using unconventional precursors in the form of deep eutectic solvents." J. Mater. Chem. A 2, no. 41 (2014): 17387–99. http://dx.doi.org/10.1039/c4ta03266g.

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Chen, Xiang, Xiao-Ru Chen, Ting-Zheng Hou, Bo-Quan Li, Xin-Bing Cheng, Rui Zhang, and Qiang Zhang. "Lithiophilicity chemistry of heteroatom-doped carbon to guide uniform lithium nucleation in lithium metal anodes." Science Advances 5, no. 2 (February 2019): eaau7728. http://dx.doi.org/10.1126/sciadv.aau7728.

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The uncontrollable growth of lithium (Li) dendrites seriously impedes practical applications of Li metal batteries. Various lithiophilic conductive frameworks, especially carbon hosts, are used to guide uniform Li nucleation and thus deliver a dendrite-free composite anode. However, the lithiophilic nature of these carbon hosts is poorly understood. Herein, the lithiophilicity chemistry of heteroatom-doped carbon is investigated through both first principles calculations and experimental verifications to guide uniform Li nucleation. The electronegativity, local dipole, and charge transfer are proposed to reveal the lithiophilicity of doping sites. Li bond chemistry further deepens the understanding of lithiophilicity. The O-doped and O/B–co-doped carbons exhibit the best lithiophilicity among single-doped and co-doped carbons, respectively. The excellent lithiophilicity achieved by O-doping carbon is further validated by Li nucleation overpotential measurement. This work uncovers the lithiophilicity chemistry of heteroatom-doped carbons and affords a mechanistic guidance to Li metal anode frameworks for safe rechargeable batteries.

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Zhao, Chun Xia, Yun Xia Yang, Wen Chen, Paul A. Webley, Xiao Yu Li, Jin Qiao Cao, and Jing Jing Du. "Characterization and Electrochemical Properties of Nitrogen-Doped Ordered Microporous Carbons Containing Well-Dispersed Platinum Nanoparticles." Advanced Materials Research 284-286 (July 2011): 875–79. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.875.

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Ordered high surface area microporous carbon molecular sieves containing well-dispersed platinum nanoparticles have been prepared by chemical vapor deposition method. Acetonitrile was employed as carbon and nitrogen precursors to yield N-doped carbon molecular sieves. N-doped carbons have an average nitrogen content of ~ 4.1 wt%. Electrochemical tests showed that the rectangular-shaped CVs of N-doped carbons could be well retained over a wide range of scan rates (5~100 mV/s), and the CV curves presented a steep current change at the switching potentials. N-doped carbons exhibited excellent performance as an electrochemical supercapacitor with a calculated specific capacitance of 168 F/g. Meanwhile, it was noticed that a reasonable Pt loading would help to improve the capacitance. It was proposed that the polarizability or surface state modification by nitrogen doping and regular interconnected porous structure might contribute to the improvement of N-doped carbons’ electrochemical properties.

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Ahiduzzaman, Md, and A. K. M. Sadrul Islam. "PREPARATION OF CONDUCTING CARBON FROM RICE HUSK CHAR." Journal of Mechanical Engineering 43, no. 1 (July 22, 2013): 29–32. http://dx.doi.org/10.3329/jme.v43i1.15776.

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Porous carbon materials have attracted interest recently as they are potential candidates for largenumber of applications especially in catalytic supports, battery electrodes, capacitors, gas storage and biomedicalengineering applications. As porous carbons are mostly amorphous in nature, a little presence of sp2 carbonstructure enhances the possibility of using these carbon materials for wider applications involving electricalconductivity. Electrical conductivity of in porous acitivated carbon is increased by doping a suitable metal ion. Ricehusk char is choosen in this study as precursor for preparation of conducting carbon. The produced conductingcarbon exibits p-type semiconductor in character when copper, nickle, zinc and silver ions are doped. The highestelectricaal conductivity of silver ion doped material is found to be 2.84x10-2 mho/cm at 60% of ion concentration ofdoping solution. The results of this study conclude that rice husk char could be used for producing conductingcarbon and silver ion is the better among other doping materials used.DOI: http://dx.doi.org/10.3329/jme.v43i1.15776

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Mestre, Ana S., and Ana P. Carvalho. "Photocatalytic Degradation of Pharmaceuticals Carbamazepine, Diclofenac, and Sulfamethoxazole by Semiconductor and Carbon Materials: A Review." Molecules 24, no. 20 (October 15, 2019): 3702. http://dx.doi.org/10.3390/molecules24203702.

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The presence of pharmaceutical compounds in the environment is a reality that calls for more efficient water treatment technologies. Photocatalysis is a powerful technology available but the high energy costs associated with the use of UV irradiation hinder its large scale implementation. More sustainable and cheaper photocatalytic processes can be achieved by improving the sunlight harvesting and the synthesis of semiconductor/carbon composites has proved to be a promising strategy. Carbamazepine, diclofenac, and sulfamethoxazole were selected as target pharmaceuticals due to their recalcitrant behavior during conventional wastewater treatment and persistence in the environment, as properly reviewed. The literature data on the photocatalytic removal of carbamazepine, diclofenac, and sulfamethoxazole by semiconductor/carbon materials was critically revised to highlight the role of the carbon in the enhanced semiconductor performance under solar irradiation. Generally it was demonstrated that carbon materials induce red-shift absorption and they contribute to more effective charge separation, thus improving the composite photoactivity. Carbon was added as a dopant (C-doping) or as support or doping materials (i.e., nanoporous carbons, carbon nanotubes (CNTs), graphene, and derived materials, carbon quantum dots (CQDs), and biochars) and in the large majority of the cases, TiO2 was the semiconductor tested. The specific role of carbon materials is dependent on their properties but even the more amorphous forms, like nanoporous carbons or biochars, allow to prepare composites with improved properties compared to the bare semiconductor. The self-photocatalytic activity of the carbon materials was also reported and should be further explored. The removal and mineralization rates, as well as degradation pathways and toxicity of the treated solutions were also critically analyzed.

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Zhou, Jin, and Shu Ping Zhuo. "Capacitive Performance of Ordered Mesoporous Carbons in Ionic Liquids." Advanced Materials Research 284-286 (July 2011): 2086–89. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.2086.

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Ordered mesoporous carbons (BOMC) were prepared by doping boric acid using a hard-templating method, while a CMK-3 carbon (OMC) was also prepared for comparison. The capacitive performance of these two carbons was investigated in ionic liquid of EMImBF4 and EMImTSFI. As demonstrated by the structure analysis, BOMC possesses almost same surface area and pore size as OMC, while the former carbon possesses higher content of oxygen-containing groups. In ionic liquid electrolyte, the carbons mainly show typical electric double layer capacitance, and the capacitance retention ratio and ion diffusion of electrolyte is determined to the surface chemical property. BOMC present visible pseudo-capacitance due to the oxygenated groups in hydrophilic EMImBF4, while no visible pseudo-capacitive behavior was observed in hydrophobic EMImTSFI.

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Priyono, Slamet. "The Effect of Al2O3 Doped and Carbon Coated Li4Ti5O12 on Structures, Morphology and Electrochemical Performance." Journal of Technomaterials Physics 2, no. 1 (February 28, 2020): 57–62. http://dx.doi.org/10.32734/jotp.v2i1.5266.

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In this research, Li4Ti5O12 anode with doping Al2O3 and carbon coating was made to determine the effect of doping Al2O3 and carbon coating on crystal structure, morphology and electrochemical performance. Li4Ti5O12 anode material consisting of LiOH.H2O and TiO2 was made with various samples of LTO without doping, LTO doped carbon, LTO doping Al2O3 and carbon using the solid state reaction method. All raw materials are mixed and milled using a Planetary Ball Miller for 2 hours then crushed to become a precursor to Li4Ti5O12. The Li4Ti5O12 precursor was sintered at 850°C for 4 hours. The final product was characterized using X-Ray Diffraction (XRD) to determine the formation of Li4Ti5O12 phases, Scanning Electron Microscopy (SEM) to analyze the morphology formed, and Cyclic Voltammetry to determine electrochemical performance. The results of XRD characterization were formed in the Lithium Titanium Oxide (Li4Ti5O12), Dilithium Titanate (Li2TiO3), and Rutile (TiO2) phases. The SEM characterization results on LTO doping carbon, LTO doping Al2O3 and carbon showed a coarser texture compared to the LTO without doping which had a fine texture. The electrochemical performance produced in LTO coating carbon has a slender redox peak in the first cycle, this shows that LTO coating carbon has good electrochemical performance compared to the Al2O3 and carbon doping LTO samples.

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Lázaro, M. J., C. Alegre, M. J. Nieto-Monge, D. Sebastián, M. E. Gálvez, E. Pastor, and R. Moliner. "Nitrogen Doped and Functionalized Carbon Materials as Supports for Catalysts in Electro-Oxidation of Methanol." Advances in Science and Technology 93 (October 2014): 41–49. http://dx.doi.org/10.4028/www.scientific.net/ast.93.41.

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The objective of this work is to study the behavior of Nitrogen-doped carbons as supports of catalysts for the electro-oxidation of methanol. Two carbon materials have been considered: a) carbon xerogels (CXG), highly mesoporous, whose porosity and pore size distribution are easily performed during the synthesis method; b) carbon nanofibers (CNF), which have a high electrical conductivity, good behavior in high temperature conditions and resistance to acid/basic media. Meanwhile, a commercial carbon black (Vulcan XC72R) which is commonly used in manufacturing of electrocatalysts fuel cells was used for comparison. Nitrogen was introduced into the CXG during the synthesis process, what is commonly referred as doping, by including melamine as a reactant. In contrast, N-groups were created over CNF by post-treatment with: ammonia (25%), urea (98%), melamine (99%) and ethylenediamine (99.5%), with a carbon: nitrogen molar ratio 1:0.6. N-containing carbon materials were characterized by elemental analysis, nitrogen adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), SEM-EDX and TEM to determinate the amount and forms of nitrogen introduced. Pt-catalysts were prepared by the microemulsion method. The influence of the nitrogen doping and functionalization on the catalytic behavior in the electrochemical oxidation of methanol was evaluated by different physicochemical and electrochemical analysis.

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Bandosz, Teresa J. "Beyond Adsorption: The Effect of Sulfur Doping on Emerging Applications of Nanoporous Carbons." Eurasian Chemico-Technological Journal 18, no. 4 (February 18, 2017): 233. http://dx.doi.org/10.18321/ectj466.

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Recently we have directed our attention to new applications of “old” materials, nanoporous carbons, as photocatalysts for oxidation of dibenzothiophenes, as water splitting catalysts, as gas sensors and as photosensitizers. Our inspiration was in graphene science. We found that both surface chemistry and porosity are crucial factors determining the specific performance. Since the effects are synergistic, it is not possible to totally separate the influence of these two factors. In terms of photoactivity and photosensitivity, surface chemistry was found as having the predominant effect on the catalytic performance. Sulfur containing groups were indicated as playing a major role in these processes. Of course physical adsorption was necessary to take place on the surface before further reactions promoted by absorption of photons occurred. Since some level of conductivity of the carbon matrix is important for an electron transfer, formation of radicals, and active oxygen species, the presence of sp2 graphitic dots of 10 nm in size in the carbon matrix enhanced the photoactive performance. In the case of gas sensing where the reversibility of the signal is important, physical adsorption was a predominant factor. Here the specific polar or electrostatic interactions enhance the sensitivity and affect markedly the selectivity. A minireview of our recent work on these two emerging topics, photoactivity of carbon and their sensing application, is presented in this paper. The emphasis is on the importance of both, specific surface chemistry and developed porosity. The latter is a unique factor, which differentiates the performance of porous carbons from that of nanoforms of carbons such as graphene or carbon nanotubes. Keywords: nanoporous carbon, photoactivity, catalytic oxidations, water splitting, gas sensing, surface chemistry, porosity, photosensitivity

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Reis, Glaydson Simões dos, Helinando Pequeno de Oliveira, Sylvia H. Larsson, Mikael Thyrel, and Eder Claudio Lima. "A Short Review on the Electrochemical Performance of Hierarchical and Nitrogen-Doped Activated Biocarbon-Based Electrodes for Supercapacitors." Nanomaterials 11, no. 2 (February 7, 2021): 424. http://dx.doi.org/10.3390/nano11020424.

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Cheap and efficient carbon electrodes (CEs) for energy storage systems (ESS) such as supercapacitors (SCs) and batteries are an increasing priority issue, among other things, due to a globally increasing share of intermittent electricity production (solar and wind) and electrification of transport. The increasing consumption of portable and non-portable electronic devices justifies research that enables environmentally and economically sustainable production (materials, processing techniques, and product design) of products with a high electrochemical performance at an acceptable cost. Among all the currently explored CEs materials, biomass-based activated carbons (AC) present enormous potential due to their availability and low-cost, easy processing methods, physicochemical stability, and methods for self-doping. Nitrogen doping methods in CEs for SCs have been demonstrated to enhance its conductivities, surface wettability, and induced pseudocapacitance effect, thereby delivering improved energy/power densities with versatile properties. Herein, a short review is presented, focusing on the different types of natural carbon sources for preparing CEs towards the fabrication of SCs with high electrochemical performance. The influences of ACs’ pore characteristics (micro and mesoporosity) and nitrogen doping on the overall electrochemical performance (EP) are addressed.

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Mirzaeian, Mojtaba, Qaisar Abbas, Michael R. C. Hunt, and Peter Hall. "Pseudocapacitive Effect of Carbons Doped with Different Functional Groups as Electrode Materials for Electrochemical Capacitors." Energies 13, no. 21 (October 26, 2020): 5577. http://dx.doi.org/10.3390/en13215577.

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In this study, RF-based un-doped and nitrogen-doped aerogels were produced by polymerisation reaction between resorcinol and formaldehyde with sodium carbonate as catalyst and melamine as the nitrogen source. Carbon/activated carbon aerogels were obtained by carbonisation of the gels under inert atmosphere (Ar) followed by activation of the carbons under CO2 at 800 °C. The BET analysis of the samples showed a more than two-fold increase in the specific Surf. area and pore volume of carbon from 537 to 1333 m2g−1 and 0.242 to 0.671 cm3g−1 respectively after nitrogen doping and activation. SEM and XRD analysis of the samples revealed highly porous amorphous nanostructures with denser inter-particle cross-linked pathways for the activated nitrogen-doped carbon. The X-Ray Photoelectron Spectroscopy (XPS) results confirmed the presence of nitrogen and oxygen heteroatoms on the Surf. and within the carbon matrix where improvement in wettability with the drop in the contact angle from 123° to 80° was witnessed after oxygen and nitrogen doping. A steady drop in the equivalent series (RS) and charge transfer (RCT) resistances was observed by electrochemical measurements after the introduction of nitrogen and oxygen heteroatoms. The highest specific capacitance of 289 Fg−1 with the lowest values of 0.11 Ω and 0.02 Ω for RS and RCT was achieved for nitrogen and oxygen dual-doped activated carbon in line with its improved Surf. chemistry and wettability, and its enhanced conductivity due to denser inter-particle cross-linked pathways.

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Wassner, Maximilian, Markus Eckardt, Andreas Reyer, Thomas Diemant, Michael S. Elsaesser, R. Jürgen Behm, and Nicola Hüsing. "Synthesis of amorphous and graphitized porous nitrogen-doped carbon spheres as oxygen reduction reaction catalysts." Beilstein Journal of Nanotechnology 11 (January 2, 2020): 1–15. http://dx.doi.org/10.3762/bjnano.11.1.

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Amorphous and graphitized nitrogen-doped (N-doped) carbon spheres are investigated as structurally well-defined model systems to gain a deeper understanding of the relationship between synthesis, structure, and their activity in the oxygen reduction reaction (ORR). N-doped carbon spheres were synthesized by hydrothermal treatment of a glucose solution yielding carbon spheres with sizes of 330 ± 50 nm, followed by nitrogen doping via heat treatment in ammonia atmosphere. The influence of a) varying the nitrogen doping temperature (550–1000 °C) and b) of a catalytic graphitization prior to nitrogen doping on the carbon sphere morphology, structure, elemental composition, N bonding configuration as well as porosity is investigated in detail. For the N-doped carbon spheres, the maximum nitrogen content was found at a doping temperature of 700 °C, with a decrease of the N content for higher temperatures. The overall nitrogen content of the graphitized N-doped carbon spheres is lower than that of the amorphous carbon spheres, however, also the microporosity decreases strongly with graphitization. Comparison with the electrocatalytic behavior in the ORR shows that in addition to the N-doping, the microporosity of the materials is critical for an efficient ORR.

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Nairat, Mazen, and Jamal A. Talla. "Electronic properties of Aluminum Doped Carbon Nanotubes with Stone Wales Defects: Density Functional Theory -=SUP=-*-=/SUP=-." Физика твердого тела 61, no. 10 (2019): 1940. http://dx.doi.org/10.21883/ftt.2019.10.48273.18.

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AbstractAl-doped single wall carbon nanotube with Stone Wales defect was theoretically analyzed, two different orientations of chiral (8, 4) carbon nanotubes was doped among the joints of defective carbon rings. Density functional theory was implemented to study structural and electronic properties of Al-doped chiral carbon nanotubes. Doping bond lengths as well as their geometrical structure were determined at the different orientations. The electronic properties were also illustrated by evaluation band of the gap energies at each possible doping site. Our results indicated that not only Al-doping tune the band structure, but also dopant site played a crucial rule on manipulating physical properties of chiral carbon nanotubes.

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Kubicka, Marcelina, Monika Bakierska, Krystian Chudzik, Michał Świętosławski, and Marcin Molenda. "Nitrogen-Doped Carbon Aerogels Derived from Starch Biomass with Improved Electrochemical Properties for Li-Ion Batteries." International Journal of Molecular Sciences 22, no. 18 (September 14, 2021): 9918. http://dx.doi.org/10.3390/ijms22189918.

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Among all advanced anode materials, graphite is regarded as leading and still-unrivaled. However, in the modern world, graphite-based anodes cannot fully satisfy the customers because of its insufficient value of specific capacity. Other limitations are being nonrenewable, restricted natural graphite resources, or harsh conditions required for artificial graphite production. All things considered, many efforts have been made in the investigation of novel carbonaceous materials with desired properties produced from natural, renewable resources via facile, low-cost, and environmentally friendly methods. In this work, we obtained N-doped, starch-based carbon aerogels using melamine and N2 pyrolysis as the source of nitrogen. The materials were characterized by X-ray powder diffraction, elemental analysis, X-ray photoelectron spectroscopy, galvanostatic charge–discharge tests, cyclic voltammetry, and electrochemical impedance spectroscopy. Depending on the doping method and the nitrogen amount, synthesized samples achieved different electrochemical behavior. N-doped, bioderived carbons exhibit far better electrochemical properties in comparison with pristine ones. Materials with the optimal amount of nitrogen (such as MCAGPS-N8.0%—carbon aerogel made from potato starch modified with melamine and CAGPS-N1.2%—carbon aerogel made from potato starch modified by N2 pyrolysis) are also competitive to graphite, especially for high-performance battery applications. N-doping can enhance the efficiency of Li-ion cells mostly by inducing more defects in the carbon matrix, improving the binding ability of Li+ and charge-transfer process.

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Wang, Rui, Zong Qing Ma, and Hui Yang. "Study on the Carbon Doping of Sugar Added MgB₂ Superconductors Prepared by Low Temperature Sintering." Advanced Materials Research 998-999 (July 2014): 91–94. http://dx.doi.org/10.4028/www.scientific.net/amr.998-999.91.

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With sugar as an addition, the active carbon released from sugar can lead to the effective carbon doping in MgB2 superconductors only under the condition of high temperature sintering. However, this kind of carbon doping cannot occur at low temperature sintering condition. The reason is that the carbon released from the decomposition reaction of the sugar added in MgB2 has very low chemical activity during low temperature sintering process, which is similar with the results of elemental carbon or graphite doping directly. Thus, only the sintering temperature reaches a certain temperature or more (generally greater than 700oC), the carbon can possess sufficiently high chemical activity and go into the lattice of MgB2 to replace the B. In the condition of low temperature, it is difficult to form an effective carbon-doped.

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Wang, Ya Wen, Shou Gang Chen, Lan Li, and Yan Sheng Yin. "First-Principles Study of Lithium Absorption in Boron- or Silicon-Doped Single-Walled Carbon Nanotubes." Advanced Materials Research 79-82 (August 2009): 613–16. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.613.

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The lithium absorption energies and electronic structures of boron- or silicon-doped single-walled carbon nanotubes (SWCNT) were investigated using ﬁrst-principles calculations based on the density-functional theory. As B and Si doping carbon nanotubes, the lithium atom adsorption energies decrease. The effects of B and Si doping are different on the lithium atomic adsorption. B-doping forms an electron-deﬁcient structure in SWCNT. While the Si-doping forms a highly reactive center. The calculations suggest that boron- and silicon-doping in SWCNT will improve Li absorption performance.

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Stefanovich, V. A., S. V. Borisov, and A. V. Stefanovich. "The influence of nitrogen content on the amount of austenite in the structure of the deposited coatings obtained from diffusionsgleichung shavings of steel Р6M5." Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no. 1 (April 10, 2019): 108–11. http://dx.doi.org/10.21122/1683-6065-2019-1-108-111.

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The article presents the results on the structure formation of deposited coatings obtained from steel chips P6M5 subjected to diffusion nitrogen-carbon doping. It was found that the diffusion doping with nitrogen-carbon steel chip waste P6M5 carbon content in them varies between 1.75–3.14%, nitrogen – 0.43–1.24%. The phase composition includes phases: a-Fe, M6C, Fe3C, (Cr, Fe)2N1–x, Fe3N, Cr0.63C0.35N0.03, M4(C, N) depending on the temperature and time of diffusion doping. When surfacing these materials in the deposited coating contains carbide-forming elements 8,6–9,3%, carbon 1,04–1,94%, nitrogen 0,08–0,25%. The structure consists of carbide M23S6, martensite and austenite, while the content of austenite in dendrites can reach 70–90%. It is shown that nitrogen doping of the deposited coatings obtained from steel chips P6M5, subjected to saturation with nitrogen-carbon, more effectively increases the amount of austenite in the structure than alloying the deposited coatings with nitrogen ferroalloys.

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Zhao, Jianfeng, Kai Chen, Bing Yang, Yanni Zhang, Caixia Zhu, Yinxiang Li, Qichun Zhang, Linghai Xie, and Wei Huang. "Surficial nanoporous carbon with high pyridinic/pyrrolic N-Doping from sp3/sp2-N-rich azaacene dye for lithium storage." RSC Advances 7, no. 85 (2017): 53770–77. http://dx.doi.org/10.1039/c7ra07850a.

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Dye to carbon: Two rationally designed pyridinic/pyrrolic N-doped porous carbons as anodic materials could be achieved by carbonizing π-conjugated azaacene dye born with high ratio sp³/sp²-N.

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Morais, Rafael Gomes, Natalia Rey-Raap, José Luís Figueiredo, and Manuel Fernando Ribeiro Pereira. "Glucose-derived carbon materials with tailored properties as electrocatalysts for the oxygen reduction reaction." Beilstein Journal of Nanotechnology 10 (May 21, 2019): 1089–102. http://dx.doi.org/10.3762/bjnano.10.109.

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Nitrogen-doped biomass-derived carbon materials were prepared by hydrothermal carbonization of glucose, and their textural and chemical properties were subsequently tailored to achieve materials with enhanced electrochemical performance towards the oxygen reduction reaction. Carbonization and physical activation were applied to modify the textural properties, while nitrogen functionalities were incorporated via different N-doping methodologies (ball milling and conventional methods) using melamine. A direct relationship between the microporosity of the activated carbons and the limiting current density was found, with the increase of microporosity leading to interesting improvements of the limiting current density. Regardless of the doping method used, similar amounts of nitrogen were incorporated into the carbon structures. However, significant differences were observed in the nitrogen functionalities according to the doping method applied: ball milling appeared to originate preferentially quaternary and oxidized nitrogen groups, while the formation of pyridinic and pyrrolic groups was favoured by conventional doping. The onset potential was improved and the two-electron mechanism of the original activated sample was shifted closer to a four-electron pathway due to the presence of nitrogen. Interestingly, the high pyridinic content related to a high ratio of pyridinic/quaternary nitrogen results in an increase of the onset potential, while a decrease in the quaternary/pyrrolic nitrogen ratio favors an increase in the number of electrons. Accordingly, the electrocatalyst with the highest performance was obtained from the activated sample doped with nitrogen by the conventional method, which combined the most appropriate textural and chemical properties: high microporosity and adequate proportion of the nitrogen functionalities.

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HUANG, WEN-FEI, PIN-JIUN WU, WEI-CHIH HSU, CHIH-WEI WU, K. S. LIANG, and M. C. LIN. "CARBON-DOPEDTiO2NANOTUBES: EXPERIMENTAL AND COMPUTATIONAL STUDIES." Journal of Theoretical and Computational Chemistry 12, no. 03 (April 19, 2013): 1350007. http://dx.doi.org/10.1142/s0219633613500077.

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C-doped TiO2nanotubes (NTs) with anatase structure, prepared by anodizing the polished Ti foils, were characterized using X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and synchrotron-based X-ray photoemission spectroscopy (XPS). XPS results show electron losses in C atoms, no electron change in Ti atoms, and two doping energy levels appeared in band gaps. Structural geometries, DOSs, PDOSs, and Bader charge analyses of C -doped TiO2anatase are predicted by periodic DFT calculations. Eight doping positions were taken into consideration: two substitutional cases (in oxygen and titanium sites) and six interstitial cases. We found that the interstitial carbon doping type is the most stable one, whereas the substitutional cases are rather unstable. Band-gap modifications can also be found in oxygen substitution, but not in titanium substitution. Both band-gap modification and non-band-gap modification are found in the interstitial carbon doping. In these eight C -doping systems, only the C atom in the oxygen substitution case gains electrons, 1.14 e, and others present electron losses within 0.5–4.00 e. The results of XPS measurements, DOSs calculations, and Bader charge analyses show that carbon interstitial is the most likely doping type for the C -doped TiO2NTs.

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Lei, Xue Fei, Chen Chen, Xing Li, Xiang Xin Xue, and He Yang. "Study on Ultrasonic Degradation of Methyl Orange Wastewater by Modified Steel Slag." Applied Mechanics and Materials 662 (October 2014): 125–28. http://dx.doi.org/10.4028/www.scientific.net/amm.662.125.

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In this paper, steel slag as the main raw material, modified steel slag adsorbent was prepared using steel slag and the active carbon as the starting materials. The influences of doping substance, the particle size, calcining temperature and doping ratio on the decoloration rate of methyl orange wastewater were investigated. The results showed that the decoloration rate of methyl orange can reach 93.62% when the doping substance was the activated carbon, the particle size was 120 mesh, the calcining temperature was 700°C, the doping ratio was 1:1.

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Ruiz-Garcia, Cristina, and Miguel A. Gilarranz. "Laminar N-Doped Carbon Materials from a Biopolymer for Use as a Catalytic Support for Hydrodechlorination Catalysts." Materials 14, no. 11 (June 5, 2021): 3107. http://dx.doi.org/10.3390/ma14113107.

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Nitrogen-doped porous carbons were prepared using a chitosan biopolymer as both a carbon and nitrogen precursor and metallic salts (CaCl2 and ZnCl2-KCl) as a templating agent with the aim of evaluating their performance as catalyst supports. Mixtures of chitosan and templating salts were prepared by simple grinding subjected to pyrolysis and finally washed with water to remove the salts. The resulting materials were characterized, showing that homogeneous nitrogen doping of carbon was achieved (7–9% wt.) thanks to the presence of a nitrogen species in the chitosan structure. A lamellar morphology was developed with carbon sheets randomly distributed and folded on themselves, creating slit-shaped pores. Substantial porosity was observed in both the micropore and mesopore range with a higher surface area and microporosity in the case of the materials prepared by ZnCl2-KCl templating and a larger size of mesopores in the case of ZnCl2. Catalysts with well-dispersed Pd nanoparticles (around 10 nm in diameter size) were synthesized using the chitosan-based carbons obtained both by salt templating and direct chitosan pyrolysis and tested in the aqueous phase hydrodechlorination of 4-chlorophenol. The fast and total removal of 4-chlorophenol was observed in the case of catalysts based on carbons obtained by templating with CaCl2 and ZnCl2-KCl in spite of the low metal content of the catalysts (0.25% Pd, wt.).

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Plunkett, Alexander, Katharina Kröning, and Bodo Fiedler. "Highly Optimized Nitrogen-Doped MWCNTs through In-Depth Parametric Study Using Design of Experiments." Nanomaterials 9, no. 4 (April 20, 2019): 643. http://dx.doi.org/10.3390/nano9040643.

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The in-situ nitrogen doping of multiwalled carbon nanotubes via chemical vapor deposition is investigated employing design of experiments (DoE). The establishment of empirical DoE models allowed for the prediction of product features as a function of process conditions in order to systematically synthesize tailor-made nitrogen-doped carbon nanotubes. The high informative content of this approach revealed effects of individual parameters and their interaction with each other. Hence, new valuable insights into the effect of temperature, injection rate, and carrier gas flow on the doping level were obtained which give motivation to approach further theoretical studies on the doping mechanism. Ultimately, competitive nitrogen-doped carbon nanotube features were optimized and yielded promising combinations of achieved doping level, graphitization, and aspect ratios in comparison to present literature values.

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Poliakov, Anatolii, Anatolii Dzyuba, Vadym Volokh, Artem Petryshchev, Bohdan Tsymbal, Mykhail Yamshinskij, Ivan Lukianenko, Andrey Andreev, Tamara Bilko, and Victor Rebenko. "Identification of patterns in the structural and phase composition of the doping alloy derived from metallurgical waste processing." Eastern-European Journal of Enterprise Technologies 2, no. 12 (110) (April 30, 2021): 38–43. http://dx.doi.org/10.15587/1729-4061.2021.230078.

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This paper reports a study into the structural-phase composition of the doping alloy made by processing metallurgical anthropogenic waste involving reduction smelting. This is required for determining the technological parameters that ensure an increase in the level of extraction of target elements during the processing of anthropogenic waste and for the further use of the doping alloy. It was revealed that the phase composition of the doping alloy manifested a solid solution of the doping elements and carbon in α-Fe. Cementite Fe3C and silicides Fe5Si3, FeSi, and FeSi2 were also identified. In this case, the doping elements were more likely to act as substitution atoms. It has been determined that the microstructure of the alloy consisted of several phases of different shapes and contents of the basic doping elements. Sites with an elevated iron level of up to 95.87 % by weight in the composition could be represented by the solid solution phase of the doping elements and carbon in α-Fe. The sites with a relatively high (% by weight) content of carbon (0.83‒2.17) and doping elements ‒ W, up to 39.41; Mo, up to 26.17; V, to 31.42; Cr, to 9.15 ‒ were apparently of a carbide nature. The sites with a silicon content of 0.43‒0.76 % by weight likely included silicide compounds. The alloy's characteristics make it possible to smelt steel grades without strict carbon restrictions, replacing some of the standard ferroalloys. Neither phases nor compounds with a relatively high propensity for sublimation were identified in the material produced. Therefore, there is no need to provide conditions to prevent evaporation and loss in the gas phase of the doping elements. That could increase the degree of extraction of the doping elements

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Wang, Hongwei, Guiqing Huang, Zhiwei Chen, and Weibing Li. "Carbon Self-Doped Carbon Nitride Nanosheets with Enhanced Visible-Light Photocatalytic Hydrogen Production." Catalysts 8, no. 9 (August 29, 2018): 366. http://dx.doi.org/10.3390/catal8090366.

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In this study, we prepared carbon self-doped carbon nitride nanosheets through a glucose synergic co-condensation method. In the carbon self-doped structure, the N atoms in the triazine rings were substituted by C atoms, resulting in enhanced visible-light photocatalytic hydrogen production, which is three-times higher than that of bulk carbon nitride. The enhanced photocatalytic hydrogen production was attributed to the higher charge-carrier transfer rate and widened light absorption range of the carbon nitride nanosheets after carbon self-doping. Thus, this work highlights the importance of carbon self-doping for improving the photocatalytic performance. Meanwhile, it provides a feasible method for the preparation of carbon self-doped carbon nitride without destroying the 2D conjugated backbone structures.

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Siraj, Noureen, Samantha Macchi, Brian Berry, and Tito Viswanathan. "Metal-Free Carbon-Based Supercapacitors—A Comprehensive Review." Electrochem 1, no. 4 (November 13, 2020): 410–38. http://dx.doi.org/10.3390/electrochem1040028.

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Herein, metal-free heteroatom doped carbon-based materials are being reviewed for supercapacitor and energy applications. Most of these low-cost materials considered are also derived from renewable resources. Various forms of carbon that have been employed for supercapacitor applications are described in detail, and advantages as well as disadvantages of each form are presented. Different methodologies that are being used to develop these materials are also discussed. To increase the specific capacitance, carbon-based materials are often doped with different elements. The role of doping elements on the performance of supercapacitors has been critically reviewed. It has been demonstrated that a higher content of doping elements significantly improves the supercapacitor behavior of carbon compounds. In order to attain a high percentage of elemental doping, precursors with variable ratios as well as simple modifications in the syntheses scheme have been employed. Significance of carbon-based materials doped with one and more than one heteroatom have also been presented. In addition to doping elements, other factors which play a key role in enhancing the specific capacitance values such as surface area, morphology, pore size electrolyte, and presence of functional groups on the surface of carbon-based supercapacitor materials have also been summarized.

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Li, Pei, Chuang Xing, Shijie Qu, Bin Li, and Wenzhong Shen. "Carbon Dioxide Capturing by Nitrogen-Doping Microporous Carbon." ACS Sustainable Chemistry & Engineering 3, no. 7 (June 18, 2015): 1434–42. http://dx.doi.org/10.1021/acssuschemeng.5b00291.

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Лундин, В. В., А. В. Сахаров, Е. Е. Заварин, Д. А. Закгейм, Е. Ю. Лундина, П. Н. Брунков, and А. Ф. Цацульников. "Изолирующие слои GaN, совместно легированные железом и углеродом." Письма в журнал технической физики 45, no. 14 (2019): 36. http://dx.doi.org/10.21883/pjtf.2019.14.48022.17738.

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Surface morphology and conductivity properties of semiinsulating GaN epitaxial layers are studied. Improvement of insulating properties with carbon or iron doping level increase is limited by morphology deterioration. Morphology development is different for these two cases. Co-doping with carbon and iron allows keeping planarity with significant improvement of insulating properties.

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Dayana, K., A. N. Fadzilah, and Mohamad Rusop. "Iodine Doping of Amorphous Carbon Thin Films Deposited by Thermal CVD." Advanced Materials Research 626 (December 2012): 834–38. http://dx.doi.org/10.4028/www.scientific.net/amr.626.834.

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A simple thermal chemical vapor deposition method is employed for the deposition of amorphous carbon thin films by natural precursor camphor oil onto the glass substrates and the iodine doping process. In this work, we have studied the effect of iodine doping on the evolution of electrical properties and the optical and structural properties of amorphous carbon thin films. The amorphous carbon thin films were characterized by using Raman spectroscopy, UV-VIS-NIR spectroscopy, current-voltage (I-V) measurement, Fourier transform infrared (FTIR) and FESEM. The I-V study reveals that the electrical conductivity was increased with the iodine doping. The iodine doped thin films induced graphitization by decreasing the optical band gap. Raman and FTIR result indicates that amorphous carbon thin films consist of a mixture of sp2 and sp3 bonded carbon atoms. The FESEM shows the amorphous nature of the thin films.

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30

Arkharova, I. V., and I. V. Zaporotskova. "Doping of Petroleum, Oil and Lubricants with Carbon Nanotubes as a Way to Improve the Performance of POL." Eurasian Chemico-Technological Journal 17, no. 4 (April 2, 2016): 295. http://dx.doi.org/10.18321/ectj273.

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It is assumed that carbon nanotubes can be used as an additive, which will improve the operational properties and functional characteristics of lubricants. The doping of petroleum, oil and lubricants – semi – synthetic engine oil – with the carbon nanotubes, taken in various wt.% of additives, was carried out: 0.01; 0.1; 0.5 wt.%. The following physical and chemical characteristics were investigated: 1) viscosity of composite mix at a temperature of T = 25 °C (an initial state); 2) viscosity of composite mix after its aging at T = 160 °C on the mode of oxidation of the investigated samples of composite mix during 24 h; 3) the oxidation stability has been determined by the «acidity» and «acid number» parameters, these parameters have been carried out for the investigated samples of composite mix in an initial state and after aging. We assumed that doping of oil with carbon nanotubes will change some of oil’s properties such as an indicator of viscosity, and chemical stability. The way of development functional and operational characteristics of lubricants by doping with carbon nanotubes was suggested. Results of researches showed that doping of carbon nanotubes causes change of such physical and chemical characteristics of lubricant as viscosity, acidity and acid number, alkaline parameter. Doping of lubricant with carbon nanotubes stops oxidation process and also leads to decrease of acidity and acid number in an initial state and for a state after aging. Besides, the carbon nanotube’s presence has increased alkaline parameter after aging of composite mix that provides ability of oil to neutralize collateral sulphurous products and after aging during its exploitation. Thus, the researches proved positive influence of carbon nanotubes on the main functional characteristics of lubricants that allow us to recommend CNTs as new additives of liquid lubricant composite mixes.

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Ewels, C. P., and M. Glerup. "Nitrogen Doping in Carbon Nanotubes." Journal of Nanoscience and Nanotechnology 5, no. 9 (September 1, 2005): 1345–63. http://dx.doi.org/10.1166/jnn.2005.304.

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32

Terrones, M., N. Grobert, M. Terrones, H. Terrones, P. M. Ajayan, F. Banhart, X. Blase, et al. "Doping and connecting carbon nanotubes." Molecular Crystals and Liquid Crystals 387, no. 1 (January 2002): 51–62. http://dx.doi.org/10.1080/10587250215249.

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33

Ortega-Franqueza, María, Svetlana Ivanova, María Isabel Domínguez, and Miguel Ángel Centeno. "Mesoporous Carbon Production by Nanocasting Technique Using Boehmite as a Template." Catalysts 11, no. 9 (September 21, 2021): 1132. http://dx.doi.org/10.3390/catal11091132.

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A series of mesoporous carbonaceous materials were synthesized by the nanocasting technique using boehmite as a template and glucose as a carbon precursor. After pyrolysis and template removal, the resulting material is a mesoporous carbon that can be additionally doped with N, B and K during prepyrolysis impregnation. In addition, the influence of doping on the morphology, crystallinity and stability of the synthesized carbons was studied using X-ray diffraction, nitrogen physisorption, thermogravimetry, Raman and IR spectroscopy and transmission electron microscopy. While the nanocasting process is effective for the formation of mesopores, KOH and urea do not modify the textural properties of carbon. The use of H3PO4 as a dopant, however, led to the formation of an AlPO4 compound and resulted in a solid with a lower specific surface area and higher microporosity. All doped solids present higher thermal stability as a positive effect of the introduction of heteroatoms to the carbon skeleton. The phosphorus-doped sample has better oxidation resistance, with a combustion temperature 120–150 °C higher than those observed for the other materials.

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34

Wang, Leini, Fei Lu, and Fanming Meng. "Synthesis and Photocatalytic Activity of TiOXPowders with Different Oxygen Defects." International Journal of Photoenergy 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/208987.

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The novel carbon- or chromium-doped TiOXphotocatalysts with different oxygen defects were synthesized by mechanochemical technique and heating process. The samples were characterized by X-ray diffraction, UV-vis spectrophotometer, and fluorescence spectrometer. Carbon and chromium species were incorporated into TiOXcrystal matrix. The mass fraction of Ti7O13in TiOXphotocatalysts could be tunable through carbon or chromium doping. The mass fraction of Ti7O13could be an indication of the degree of oxygen defects (the concentration of Ti3+) in the TiOX. The degree of oxygen defects increased for carbon doping, while the degree of oxygen defects decreased for chromium doping. The photocatalytic activity measurement results showed that photodegradation rate of methyl orange reached the maximum value with mass fraction of Ti7O13of about 66.93%, but the photodegradation rate decreased when mass fraction of Ti7O13is raised further. In addition, the origin of absorption in the visible spectral range for carbon-doped TiOXas well as the effect of band gap on photocatalytic activity has also been discussed in this paper.

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35

Dayana, K., A. N. Fadzilah, A. Ishak, and Mohamad Rusop Mahmood. "Properties of Iodine Doped Amorphous Carbon Thin Films Grown by Thermal CVD." Advanced Materials Research 667 (March 2013): 294–99. http://dx.doi.org/10.4028/www.scientific.net/amr.667.294.

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Thin film of undoped and doped amorphous carbon has been achieved using the simple thermal CVD system in an ambient gas of Ar and Ar with I2, respectively. The electrical and optical properties of the iodine doped amorphous carbon (a-C:I) thin films were studied. The incorporation of iodine into the amorphous carbon thin film results in increase of electrical conductivity as doping temperature increase up to 400°C, which indicates that doping effect of iodine. Heterojuction is confirmed by rectifying current-voltage characteristics of a-C:I/n-Si junction. The decreasing of optical band gap from 0.54 to 0.25 eV after iodine doping was determined which contribute to induce graphitization in the films. Raman result indicates that sp2 and sp3 bonded carbon atoms were dominated in the both with and without iodine doped thin films.

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36

MIMILA-ARROYO, J., and S. W. BLAND. "HYDROGEN CO-DOPING IN III-V SEMICONDUCTORS: DOPANT PASSIVATION AND CARBON REACTIVATION KINETICS IN C-GaAs." Modern Physics Letters B 15, no. 17n19 (August 20, 2001): 585–92. http://dx.doi.org/10.1142/s0217984901002063.

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Hydrogen in semiconductors is an electrically active impurity whose interaction with lattice point defects and impurities, might produce a strong modification on their physical behavior, changing some material properties, influencing as well, device performance. In this work we will review the main effects of hydrogen co-doping on the properties crystalline semiconductors, discuss on the driving force on the process of hydrogen incorporation in carbon doped GaAs, growth in the presence of hydrogen. A detailed model on the carbon reactivation kinetics, carbon doping efficiency and carbon-hydrogen complexes behavior in MOCVD-GaAs epitaxial layers will be presented. Finally, we will discuss the probable relation between the beta evolution of the high frequency and high power n-GaInP/p-GaAs/n-GaAs hetero-junction bipolar transistor (HBT), and the hydrogen co-doping of the C:GaAs, constituting its base.

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37

Cheng, Wei, Chen Cheng, and Baolin Ke. "The Effect of Carbon Defects in the Coal–Pyrite Vacancy on the Electronic Structure and Optical Properties: A DFT + U Study." Minerals 10, no. 9 (September 15, 2020): 815. http://dx.doi.org/10.3390/min10090815.

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Pyrite is a mineral often associated with coal in coal seams and is a major source of sulfur in coal. Coal–pyrite is widely distributed, easily available, low-cost, and non-toxic, and has high light absorption coefficient. So, it shows potential for various applications. In this paper, the density-functional theory (DFT + U) is used to construct coal–pyrite with carbon doped in the sulfur and iron vacancies of pyrite. The effects of different carbon defects, different carbon doping concentrations, and different doping distributions in the same concentration on the electronic structure and optical properties of coal–pyrite were studied. The results show that the absorption coefficient and reflectivity of coal–pyrite, when its carbon atom substitutes the iron and sulfur atoms in the sulfur and iron vacancies, are significantly higher than those of the perfect pyrite, indicating that coal–pyrite has potential for application in the field of photovoltaic materials. When carbon is doped in the sulfur vacancy, this impurity state reduces the width of the forbidden band; with the increase in the doping concentration, the width of the forbidden band decreases and the visible-light absorption coefficient increases. The distribution of carbon impurities impacts the band gap but has almost no effect on the light absorption coefficient, complex dielectric function, and reflectivity, indicating that the application of coal–pyrite to photovoltaic materials should mainly consider the carbon doping concentration instead of the distribution of carbon impurities. The research results provide a theoretical reference for the application of coal–pyrite in the field of photoelectric materials.

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38

Uriburu-Gray, María, Aránzazu Pinar-Serrano, Gokhan Cavus, Etienne Knipping, Christophe Aucher, Aleix Conesa-Cabeza, Amro Satti, David Amantia, and Sandra Martínez-Crespiera. "Mesoporous Carbons from Polysaccharides and Their Use in Li-O2 Batteries." Nanomaterials 10, no. 10 (October 15, 2020): 2036. http://dx.doi.org/10.3390/nano10102036.

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Previous studies have demonstrated that the mesoporosity of carbon material obtained by the Starbon® process from starch-formed by amylose and amylopectin can be tuned by controlling this ratio (the higher the amylose, the higher the mesoporosity). This study shows that starch type can also be an important parameter to control this mesoporosity. Carbons with controlled mesoporosity (Vmeso from 0.1–0.7 cm3/g) have been produced by the pre-mixing of different starches using an ionic liquid (IL) followed by a modified Starbon® process. The results show that the use of starch from corn and maize (commercially available Hylon VII with maize, respectively) is the better combination to increase the mesopore volume. Moreover, “low-cost” mesoporous carbons have been obtained by the direct carbonization of the pre-treated starch mixtures with the IL. In all cases, the IL can be recovered and reused, as demonstrated by its recycling up to three times. Furthermore, and as a comparison, chitosan has been also used as a precursor to obtain N-doped mesoporous carbons (5.5 wt% N) with moderate mesoporosity (Vmeso = 0.43 cm3/g). The different mesoporous carbons have been tested as cathode components in Li-O2 batteries and it is shown that a higher carbon mesoporosity, produced from starch precursor, or the N-doping, produced from chitosan precursor, increase the final battery cell performance (specific capacity and cycling).

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39

Zhang, Fu, Yanfu Lu, Daniel S. Schulman, Tianyi Zhang, Kazunori Fujisawa, Zhong Lin, Yu Lei, et al. "Carbon doping of WS2 monolayers: Bandgap reduction and p-type doping transport." Science Advances 5, no. 5 (May 2019): eaav5003. http://dx.doi.org/10.1126/sciadv.aav5003.

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Chemical doping constitutes an effective route to alter the electronic, chemical, and optical properties of two-dimensional transition metal dichalcogenides (2D-TMDs). We used a plasma-assisted method to introduce carbon-hydrogen (CH) units into WS2 monolayers. We found CH-groups to be the most stable dopant to introduce carbon into WS2, which led to a reduction of the optical bandgap from 1.98 to 1.83 eV, as revealed by photoluminescence spectroscopy. Aberration corrected high-resolution scanning transmission electron microscopy (AC-HRSTEM) observations in conjunction with first-principle calculations confirm that CH-groups incorporate into S vacancies within WS2. According to our electronic transport measurements, undoped WS2 exhibits a unipolar n-type conduction. Nevertheless, the CH-WS2 monolayers show the emergence of a p-branch and gradually become entirely p-type, as the carbon doping level increases. Therefore, CH-groups embedded into the WS2 lattice tailor its electronic and optical characteristics. This route could be used to dope other 2D-TMDs for more efficient electronic devices.

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40

Binitha, Naraya Nan, Zahira Yaakob, P. P. Silija, P. V. Suraja, and S. M. Tasirin. "Effect of Co-Doping of Nano Silver, Carbon and Nitrogen on Titania on the Visible Light Activity for Methylorange Degradation." Defect and Diffusion Forum 312-315 (April 2011): 776–81. http://dx.doi.org/10.4028/www.scientific.net/ddf.312-315.776.

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Co-doping of nanosilver, carbon and nitrogen is done on titania to get improved photodegradation of pollutants when compared to single doping. Anion doping extends the absorption of TiO2 to the visible region; whereas noble metal NP doping prevents the recombination of photoinduced electrons and holes. Doped TiO2 prepared using sol gel method allows efficient dispersion of nano silver and thus enhances the photodegradability. X-ray Diffraction analysis shows the efficient dispersion of incorporated nano silver over anatase TiO2. The visible light absorption is confirmed from UV-Vis Diffuse Reflectance spectral studies. Photocatalytic activity is investigated by the degradation of methyl orange as a model pollutant. Efficient degradation in visible light shows the synergetic effect of carbon and nitrogen doping as well as nano silver loading on the performance of TiO2.

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41

Sun, Zongzhao, Wu Wang, Qianwen Chen, Yayun Pu, Heng He, Weiman Zhuang, Jiaqing He, and Limin Huang. "A hierarchical carbon nitride tube with oxygen doping and carbon defects promotes solar-to-hydrogen conversion." Journal of Materials Chemistry A 8, no. 6 (2020): 3160–67. http://dx.doi.org/10.1039/c9ta13012h.

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42

Nishizawa, Shin Ichi, and Michel Pons. "Numerical Analysis of Growth Condition on SiC-CVD in the Horizontal Hot-Wall Reactor." Materials Science Forum 483-485 (May 2005): 53–56. http://dx.doi.org/10.4028/www.scientific.net/msf.483-485.53.

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Growth, etching, and doping features of SiC-CVD in a horizontal hot-wall reactor were numerically analyzed using the improved heterogeneous model. The improved model was able to explain the growth and etching features accurately. In addition, we propose the surface flux, surface carbon and silicon concentration, and its ratio as the universal parameter of the SiC-CVD process. Concerning doping features, the improved model showed that nitrogen and aluminum doping incorporation could be explained by the site competition model, while taking into account the amount of surface silicon and surface carbon, respectively.

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43

Burungale, V. V., Hyojung Bae, A. S. Kamble, J. H. Kim, P. S. Patil, and J. S. Ha. "Studies on interstitial carbon doping from a Ti precursor in a hierarchical TiO2 nanostructured photoanode by a single step hydrothermal route." RSC Advances 10, no. 48 (2020): 28492–500. http://dx.doi.org/10.1039/d0ra04744a.

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Jana, Malay, Anjan Sil, and Subrata Ray. "Influence of Melting of Transition Metal Oxides on the Morphology of Carbon Nanostructures." Advanced Materials Research 585 (November 2012): 159–63. http://dx.doi.org/10.4028/www.scientific.net/amr.585.159.

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Different types of carbon nanostructure materials have been grown on nano-sized transition metal oxide based catalyst particles by catalytic chemical vapour deposition. The present investigation reveals an important role of melting or surface melting of oxide catalysts for the growth of carbon nanostructure materials. In the reducing environment prevailing during the growth of nanostructures, oxide catalysts are reduced to metals, which may act as a template for the growth of carbon nanostructure materials. Flow rate of acetylene gas is crucial in catalyzing the growth, as high flow rate of acetylene may cover the catalyst particles with a layer of decomposed carbon, rendering the particles incapable of playing the role of catalyst. The size of the catalyst and the extent of melting, determined primarily by the extent of doping, are important in deciding whether the conditions are favourable for the growth of multi walled carbon nanotube, nanofiber or other nanostructures. Smaller particle size and low doping level favour the growth of multi walled carbon nanotube while growth of nanofiber is commonly observed with larger particles and higher doping level. The size (i.e. diameter) of the nanostructures growing around the catalyst is proportional to the particle size of the catalyst.

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45

Karima, Rizka, and Nurmilatina Nurmilatina. "Pengaruh Variasi Aktivator dan Doping terhadap Nilai Daya Hantar Listrik dan Karakterisasi Karbon dari Bambu (Effect of Activator and Doping Variation on The Electrical Conductivity and Carbon Characteristics of Bamboo)." Jurnal Riset Industri Hasil Hutan 10, no. 1 (June 1, 2018): 11–20. http://dx.doi.org/10.24111/jrihh.v10i1.3683.

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An added value of bamboo charcoal that is commonly used as an energy source could be increased by the addition of activator and metal doping. The objective of this research was to analyze the effect of the addition of activator and doping to the electrical conductivity and carbon characteristics for a raw material of bio-battery. Bamboo plantsused in this experiment were buluh, haur, and betung. Bamboo was carbonized inthe temperature range between 500oC and 600oC by pyrolysis method. Obtained charcoal was activated using two types of chemicals, KOH and HNO3, and then was doped with Zn and Ni. Furthermore, obtained carbon was made into nanoparticles using High Energy Milling. The structure and properties of the carbon were tested using PSA, SEM, and XRD; and the conductivity was also tested. The smallest particle size was obtained from ‘buluh’ bamboo charcoal with HNO3 activation and without a doping at 1030 nm. The diffractogram and topography of the bamboo charcoal varied depending on the metal doping added. The highest electrical conductivity (DHL) was obtained from betung charcoal with an activator of KOH and a doping of Zn at 7.02 mS/cm.

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46

Fujimoto, Yoshitaka. "Formation, Energetics, and Electronic Properties of Graphene Monolayer and Bilayer Doped with Heteroatoms." Advances in Condensed Matter Physics 2015 (2015): 1–14. http://dx.doi.org/10.1155/2015/571490.

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Doping with heteroatoms is one of the most effective methods to tailor the electronic properties of carbon nanomaterials such as graphene and carbon nanotubes, and such nanomaterials doped with heteroatom dopants might therefore provide not only new physical and chemical properties but also novel nanoelectronics/optoelectronics device applications. The boron and nitrogen are neighboring elements to carbon in the periodic table, and they are considered to be good dopants for carbon nanomaterials. We here review the recent work of boron and nitrogen doping effects into graphene monolayer as well as bilayer on the basis of the first-principles electronic structure calculations in the framework of the density-functional theory. We show the energetics and the electronic properties of boron and nitrogen defects in graphene monolayer and bilayer. As for the nitrogen doping, we further discuss the stabilities, the growth processes, and the electronic properties associated with the plausible nitrogen defect formation in graphene which is suggested by experimental observations.

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47

Caccamo, Sebastiano, and Rosaria Anna Puglisi. "Carbon-Free Solution-Based Doping for Silicon." Nanomaterials 11, no. 8 (August 5, 2021): 2006. http://dx.doi.org/10.3390/nano11082006.

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Molecular doping is a method to dope semiconductors based on the use of liquid solutions as precursors of the dopant. The molecules are deposited on the material, forming a self-ordered monolayer that conforms to the surfaces, whether they are planar or structured. So far, molecular doping has been used with precursors of organic molecules, which also release the carbon in the semiconductor. The carbon atoms, acting as traps for charge carriers, deteriorate the doping efficiency. For rapid and extensive industrial exploitation, the need for a method that removes carbon has therefore been raised. In this paper, we use phosphoric acid as a precursor of the dopant. It does not contain carbon and has a smaller steric footprint than the molecules used in the literature, thus allowing a much higher predetermined surface density. We demonstrate doses of electrical carriers as high as 3 × 1015 #/cm2, with peaks of 1 × 1020 #/cm3, and high repeatability of the process, indicating an outstanding yield compared to traditional MD methods.

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Zeng, Juan, Qi Cao, Bo Jing, and Xiuxiang Peng. "Hierarchical porous nitrogen doping activated carbon with high performance for supercapacitor electrodes." RSC Advances 6, no. 19 (2016): 15320–26. http://dx.doi.org/10.1039/c5ra23735a.

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LUO, FUSHENG, QINGYI SHAO, LIXIA ZHANG, JUAN ZHANG, and ZHONGLIANG PAN. "BORON/PHOSPHORUS CO-DOPING IN ZIGZAG SINGLE-WALLED CARBON NANOTUBES: A FIRST-PRINCIPLES STUDY." Modern Physics Letters B 27, no. 15 (May 21, 2013): 1350114. http://dx.doi.org/10.1142/s0217984913501145.

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By using the first-principles methods based on density function theory (DFT), the effects of boron(B)/phosphorus(P) pair co-doping on the electrical properties of zigzag single-walled carbon nanotubes (SWNTs) have been investigated. We calculated the formation energies and band structures of (6, 0) metallic and (8, 0) semiconducting SWNTs with different B/P co-doping sites and concentrations. The obtained formation energies suggest that the B/P co-doping configurations are energetically stable structures and the B and P tend to form a B–P bond. It shows that an energy gap is opened by B/P co-doping in (6, 0) metallic SWNTs and the metallic carbon nanotubes are converted into semiconductors. For the (8, 0) semiconducting SWNTs, B/P co-doping influences the band structure, but it does not change the attributes essentially and the SWNTs are still semiconducting. It was also found that the band structures depend on the doping concentration as well as the doping site of B/P pair.

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Li, Bing Zheng, Ya Bing Guo, Lai Shuan Liu, Yong Bing Xue, and De Kui Sun. "Equilibrium and Thermodynamics of Adsorption of Fe/Ac for Aniline from Dilute Solutions." Advanced Materials Research 378-379 (October 2011): 688–91. http://dx.doi.org/10.4028/www.scientific.net/amr.378-379.688.

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The effect of iron doping on physical and chemical properties of activated carbon, the effect of initial concentration and temperature on adsorption behavior of adsorbents for aniline from water, and adsorption equilibrium and thermodynamics were investigated. The results show that Fe doping obviously increase acidic oxygen-containg groups of activated carbon surface. Effect of Fe doping on adsorption capacity of aniline at the low concentration is insignificant. Equilibrium adsorption uptake decreases with an increase in adsorption temperaure. Freundlich model can better describe adsorption behavior of aniline on AC and Fe/AC. Aniline adsorption is spontaneous and exothermic.

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Journal articles on the topic 'Carbon dopin'

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