Journal articles: 'Thermogravimetric analysis (TGA), viscoelasticity, x-ray photoelectron spectroscopy (XPS)'

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Li, Tingting, Hongxia Yan, Tianye Liu, Chao Liu, and Zhengyan Chen. "Carbon Nanotubes Grafted with Hyperbranched Triazine Compounds." Nano 10, no. 01 (January 2015): 1550012. http://dx.doi.org/10.1142/s1793292015500125.

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In order to improve the dispersibility of carbon nanotubes (CNTs) in the resin matrix, CNTs grafted with hyperbranched triazine compound (HPTC–CNTs) was produced by four generations condensation reaction using cyanuric chloride and hexamethylenediamine. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), UV-Vis spectroscopy (UV-Vis) and transmission electron microscopes (TEM) were used to characterize the obtained HPTC–CNTs. The FTIR, XPS, UV-Vis and TEM analysis showed that CNTs had been successfully grafted with HPTC. The TGA showed that the content of HPTC on the surface of CNTs was about 58 wt.%. And the HPTC–CNTs had good dispersion both in water and acetone.

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Hashimov, R. F., F. A. Mikailzade, S. V. Trukhanov, N. M. Lyadov, I. R. Vakhitov, A. V. Trukhanov, and M. N. Mirzayev. "Structure and thermal analysis of Ba0.5La0.5MnO3 polycrystalline powder." International Journal of Modern Physics B 33, no. 22 (September 10, 2019): 1950244. http://dx.doi.org/10.1142/s0217979219502448.

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The structure and thermal properties of Ba[Formula: see text]La[Formula: see text]MnO3 polycrystalline powder have been investigated using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. The structural studies have shown that Ba[Formula: see text]La[Formula: see text]MnO3 compound crystallizes in perovskite structure with Pm-3m cubic symmetry group. The lattice parameters were obtained to be a = b = c = 3.9073 Å. Mass changes have been observed from thermogravimetric (TG) and differential thermogravimetric (DTG) curves obtained in a wide temperature interval of 30–950[Formula: see text]C. Free energy and enthalpy changes for all observed transformations were determined. Observed endo and exo effects.

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GUAN, MIN, HAI-PENG BI, ZUYUAN WANG, SHAOHUA BU, LING HUANG, and LI YANG. "SYNTHESIS, CHARACTERIZATION AND THE APPLICABILITY OF β-CYCLODEXTRINS FUNCTIONALIZED MESOPOROUS SBA-15 MOLECULAR SIEVES." Nano 08, no. 05 (August 18, 2013): 1350050. http://dx.doi.org/10.1142/s1793292013500501.

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Mesoporous silicas SBA-15 are modified with β-Cyclodextrins (β-CD) by simple grafting method. β-CD functionalized SBA-15 was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), nitrogen adsorption–desorption measurements, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Furthermore, the applicability of it is investigated through studying the adsorption properties of clenbuterol. It showed better adsorption capacities of clenbuterol than pure SBA-15. β-CD functionalized SBA-15 material has the potential applications in the treatment of clenbuterol contamination in food and environment science.

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Shin, Hyunjung, Yuhu Wang, Uma Sampathkumaran, Mark R. De Guire, Arthur H. Heuer, and Chaim N. Sukenik. "Pyrolysis of self-assembled organic monolayers on oxide substrates." Journal of Materials Research 14, no. 5 (May 1999): 2116–23. http://dx.doi.org/10.1557/jmr.1999.0286.

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The pyrolysis of siloxy-anchored, organic self-assembled monolayers (SAMs) on oxide substrates [titanium dioxide powder; hydrolyzed silicon dioxide on (100) silicon] was studied using x-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and mass spectroscopy (MS). Pyrolysis in air began on heating at 200 °C and was complete by 400 °C for both octadecyltrichlorosilane (OTS) and C16-thioacetate (TA) SAMs, as observed in TGA of SAM-coated TiO2 powders, and in XPS studies of TA-SAM-coated TiO2 powders and Si wafers after various heat treatments. In low-oxygen environments, pyrolysis of SAMs began at higher temperatures: between 250 and 400 °C for heating in ultrahigh vacuum (10−8 Torr) as observed in XPS studies of TA-SAMs on Si, and between 300 and 400 °C in nitrogen, as observed in TEM analysis of sulfonate SAMs under a TiO2 thin film on Si substrates.

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Bear, Joseph C., Bin Yu, Cristina Blanco-Andujar, Paul D. McNaughter, Paul Southern, Marc-Krystelle Mafina, Quentin A. Pankhurst, and Ivan P. Parkin. "A low cost synthesis method for functionalised iron oxide nanoparticles for magnetic hyperthermia from readily available materials." Faraday Discuss. 175 (2014): 83–95. http://dx.doi.org/10.1039/c4fd00062e.

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The synthesis of iron oxide nanocrystals from reagents taken from high street sources using thermal decomposition of an iron–fatty acid precursor in a high boiling point solvent in the presence of surfactants is presented. The nanocrystals were characterised using a variety of techniques including: electron microscopy, X-ray dispersive spectroscopy, infrared spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and magnetometry. Thermogravimetric analysis (TGA) is also used to compare the decomposition behaviour of iron oleate and iron palmitate, our nanoparticle precursors. The nanoparticles also exhibit shape anisotropy when prepared under optimum conditions. We show that these nanoparticles have potential in magnetic hyperthermia after transfer to aqueous media via an amphiphilic polymer.

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Tam, C. Y., and C. H. Shek. "Effects of alloying on oxidation of Cu-based bulk metallic glasses." Journal of Materials Research 20, no. 10 (October 2005): 2647–53. http://dx.doi.org/10.1557/jmr.2005.0336.

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The oxidation kinetics and the effects of alloying on the oxidation behaviors of copper-based bulk metallic glasses were studied. The oxidation kinetics, oxide compositions, and structures were investigated by thermogravimetric analysis (TGA), x-ray diffraction, x-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. Both the TGA results and the XPS depth profile measurements showed that the oxidation resistance of Cu60Zr30Ti10 bulk metallic glass was improved by adding Hf, but it deteriorated when it was alloyed with Y. The oxide phases were found to be ZrO2, Cu2O, and CuO in samples heated at 573 K while an additional metallic Cu phase was detected in the ones heated at 773 K. A porous oxide structure was observed in the (Cu0.6Zr0.3Ti0.1)98Y2 metallic glass oxidized at 673 K, and the poor oxidation resistance of the alloy is attributed to the porous structure.

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Seki, Yasemin, Ahmet Çağrı Kılınç, Ramazan Dalmış, Serhan Köktaş, and Erdal Çelik. "Characterization of Flax, Jute, and Sisal Fibers after Sodium Perborate Modification." AATCC Journal of Research 6, no. 6 (November 1, 2019): 25–31. http://dx.doi.org/10.14504/ajr.6.6.4.

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The aim of this research is to investigate sodium perborate tetrahydrate (SP) modification of cellulosic fibers. Flax, jute, and sisal fibers were treated with aqueous solutions of SP at three different concentrations. The changes in surface characteristics were analyzed using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). No significant changes in the crystallinity index for all fibers tested were observed as SP treatments only produced surface modification. SEM images showed partial removal of non-cellulosic components occurred. Increased SP concentrations led to greater surface cleaning and fiber separation, imparting a more hydrophobic surface character.

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Gao, Dawei, Lili Wang, Chunxia Wang, and Tan Chen. "Photocatalytic Self-Cleaning Cotton Fabrics Coated by Cu2(OH)PO4 under VIS/NIR Irradiation." Materials 12, no. 2 (January 11, 2019): 238. http://dx.doi.org/10.3390/ma12020238.

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In the present work, a mild strategy was employed to obtain cotton fabrics (CFs) coated with Cu2(OH)PO4 (CHP) nanoparticles to achieve self-cleaning property. The phytic acid (IP6) assisted method was employed to synthesize nanoparticles (CHP-IP6). The as-prepared coated cotton fabrics were characterized using the following techniques: Fourier-transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The CHP-IP6 coated cotton fabrics showed significant photocatalytic activity, excellent photocatalytic stability, and good discoloration of methylene blue (MB) stains when exposed to sunlight, which could have important applications as tablecloths, household apparels, and industrial workwear.

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Li, Yu Feng, Hong Chao Wang, Zhong Yuan Xiang, and Xiao Hui Gao. "Synthesis of Self-Stratifying Polyacrylate Latex Containing Silicon." Applied Mechanics and Materials 151 (January 2012): 337–40. http://dx.doi.org/10.4028/www.scientific.net/amm.151.337.

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Self-stratifying polyacrylate latex containing silicon was synthesized via semi-continuous emulsion polymerization, using organic silicon and acrylate as raw materials. Transmission electron microscope(TEM) characterization indicated that the particles were form uniform analogous core-shell structure and dynamic light scattering(DLS) analysis possessed narrow size distributions. The results of X-ray photoelectron spectroscopy(XPS) proved the propensity of silicon enrichment at film-air interface, which revealed self-stratifying phenomenon. The thermal stability of the latex films determined by thermogravimetric analysis(TGA) was increased 24 °C as the join of organic silicon.

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LI, WEIDONG, and ENYONG DING. "CHARACTERIZATION OF PET FABRICS SURFACE MODIFIED BY GRAFT CELLULOSE NANO-CRYSTAL USING TGA, FE-SEM AND XPS." Surface Review and Letters 13, no. 06 (December 2006): 819–23. http://dx.doi.org/10.1142/s0218625x06008906.

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Surface-modified Poly(ethylene terephthalate) (PET) fabrics were prepared through thionylchlorided cellulose nano-crystal (CNC) reacting with hydroxyl groups at the surface of the alkali-etched PET fabrics. X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM) and thermogravimetric analysis (TGA) were employed to study the topography, superficial ingredients and thermal properties of the composite, respectively. It was confirmed by the observation of FE-SEM that the surface of PET fabrics was covered by the immobilized CNC particles, and increasing O/C atomic ratio in XPS-spectra was found with grafting. The TGA examination indicated that CNC-g-PET had less weight loss in the range of 300–350° than alkali-treated PET fibers, which was caused by the cross-linking effect of CNC particles with multi-ended reactive groups.

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Maity, Arjun, and Suprakas Sinha Ray. "Conducting Nanocomposites of Poly(N-vinylcarbazole) with Single-Walled Carbon Nanotubes." Journal of Nanoscience and Nanotechnology 8, no. 4 (April 1, 2008): 1728–34. http://dx.doi.org/10.1166/jnn.2008.268.

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The in situ solid-state polymerization of N-vinylcarbazole (NVC) at an elevated temperature in the presence of single-walled carbon nanotubes (SWCNTs) leads to the formation of new types of composite materials, the morphology and properties of which were characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and electrical property measurements. FTIR spectroscopy and XPS studies confirmed the ability of SWCNTs to initiate the in situ polymerization of NVC monomers. FE-SEM and TEM results showed the coating of the outer surfaces of SWCNTs by the PNVC hompolymer with separation of individual SWCNTs from the bundles. Thermogravimetric analysis revealed a moderate improvement in the thermal stability of the nanocomposites at a higher temperature region relative to the base polymer. The electrical conductivity of neat polymer dramatically improved in the presence of SWCNTs. For example, dc electrical conductivity increased from 10–16–10–12 S˙cm–1 for neat PNVC to ∼10–6 S˙cm–1 for nanocomposite containing 9 wt% SWCNTs.

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Li, Weihang, Bojun Song, Shirui Zhang, Fan Zhang, Chang Liu, Nan Zhang, Huiling Yao, and Yuanchang Shi. "Using 3-Isocyanatopropyltrimethoxysilane to Decorate Graphene Oxide with Nano-Titanium Dioxide for Enhancing the Anti-Corrosion Properties of Epoxy Coating." Polymers 12, no. 4 (April 6, 2020): 837. http://dx.doi.org/10.3390/polym12040837.

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In this paper, the graphene oxide loaded with nano titanium dioxide (TiO2–GO) was synthesized through 3-isocyanatopropyltrimethoxysilane (IPTMS) and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and dispersion test. The results illustrated our modification was successful and TiO2–GO was transferred from hydrophilic to hydrophobic. That greatly enhanced the dispersity of TiO2–GO in epoxy through the observation of the coating morphology test. Moreover, the impact of TiO2–GO on anti-corrosion property in epoxy was investigated by Electrochemical Impedance Spectroscopy (EIS). Comparing to pristine particles including GO and TiO2, TiO2–GO could more significantly improve the resistance of corrosion with the help of IPTMS. Furthermore, the anti-corrosion mechanism of TiO2–GO in epoxy was tentatively proposed and discussed.

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Hodge, Stephen A., Hui Huang Tay, David B. Anthony, Robert Menzel, David J. Buckley, Patrick L. Cullen, Neal T. Skipper, Christopher A. Howard, and Milo S. P. Shaffer. "Probing the charging mechanisms of carbon nanomaterial polyelectrolytes." Faraday Discuss. 172 (2014): 311–25. http://dx.doi.org/10.1039/c4fd00043a.

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Chemical charging of single-walled carbon nanotubes (SWCNTs) and graphenes to generate soluble salts shows great promise as a processing route for electronic applications, but raises fundamental questions. The reduction potentials of highly-charged nanocarbon polyelectrolyte ions were investigated by considering their chemical reactivity towards metal salts/complexes in forming metal nanoparticles. The redox activity, degree of functionalisation and charge utilisation were quantified via the relative metal nanoparticle content, established using thermogravimetric analysis (TGA), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and X-ray photoelectron spectroscopy (XPS). The fundamental relationship between the intrinsic nanocarbon electronic density of states and Coulombic effects during charging is highlighted as an important area for future research.

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Bhise, S. C., D. V. Awale, M. M. Vadiyar, S. K. Patil, B. N. Kokare, A. V. Ghule, and S. S. Kolekar. "Controlled Synthesis of Nanostructured Nickel Oxide Thin Film for Supercapacitor Application." Advanced Science Letters 24, no. 8 (August 1, 2018): 5587–92. http://dx.doi.org/10.1166/asl.2018.12155.

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In the present work we report the controlled synthesis of NiO thin film with nano-leaves like morphology using reflux method. The synthesized NiO electrode is used as working electrode for supercapacitor application. The deposited NiO thin film was characterized using thermogravimetric (TGA) analysis, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The supercapacitor behaviour of NiO was investigated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy using 3 M KOH electrolyte. The electrochemical results show specific capacitance of 513 F g−1 at 10 mV s−1 scan rate, power density (10.44 kW kg−1), energy density (14 Wh kg−1) and 85% capacitance retention over 5000 cycles. These remarkable results indicate the importance of the NiO nano-leaves electrode in energy storage device.

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Bach, Long Giang. "PREPARATION AND CHARACTERIZATION OF SIO2/POLY(METHYL METHACRYLATE) CORE/SHELL NANOCOMPOSITES VIA RAFT POLYMERIZATION." Vietnam Journal of Science and Technology 54, no. 1A (March 16, 2018): 285. http://dx.doi.org/10.15625/2525-2518/54/1a/11839.

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This article describes the fabrication of SiO2 nanoparticles grafted with poly(methyl methacrylate) (PMMA) via a fascinating reversible addition-fragmentation chain transfer (RAFT) polymerization by adopting “grafting from” approach. The silane coupling agent, S-benzyl S’-trimethoxysilylpropyltrithiocarbonate, was anchored onto SiO2 nanoparticles in a simple procedure using a ligand exchange reaction. RAFT agents-anchored SiO2 nanoparticles were then used for the surface-initiated RAFT polymerization of MMA to fabricate structurally well-defined, core-shell SiO2-g-PMMA nanocomposites. The structure and properties of the as-synthesized nanocomposites were investigated by Fourier Transformed Infrared Spectrophotometry (FT-IR), X-ray Photoelectron Spectroscopy (XPS), Thermogravimetric analysis (TGA), Field Emission Scanning Electron Microscopy (FE-SEM).

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Xiong, Shenglin, Baojuan Xi, Weizhi Wang, Hongyang Zhou, Shuyuan Zhang, and Yitai Qian. "Preparation and Characterization of Silica-Coated ZnSe Nanowires with Thermal Stability and Photoluminescence." Journal of Nanoscience and Nanotechnology 7, no. 12 (December 1, 2007): 4494–500. http://dx.doi.org/10.1166/jnn.2007.860.

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Silica-coated ZnSe nanowires with well-controlled the thickness of sheath in the range of 10–60 nm have been synthesized through a simple sol–gel process. The thickness of silica coating could be controlled through altering reaction parameters such as volume ratio of TEOS and ammonia. XRD, high-resolution TEM, X-ray photoelectron spectroscopy (XPS), Raman spectra, thermogravimetric analysis (TGA), and photoluminescence (PL) spectra were used to characterize the core/sheath nanostructures. Room-temperature PL measurements indicate these silica-coated ZnSe nanowires remarkably improve the PL intensity. Meanwhile, the thermal stability has been enhanced greatly, which is useful for their potential applications in advanced semiconductor devices.

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Gómora-Herrera, Diana, Juan Navarrete Bolaños, Irina V. Lijanova, Octavio Olivares-Xometl, and Natalya V. Likhanova. "Study of Surface Wettability Change of Unconsolidated Sand Using Diffuse Reflectance Infrared Fourier Transform Spectroscopy and Thermogravimetric Analysis." Applied Spectroscopy 72, no. 4 (January 8, 2018): 562–72. http://dx.doi.org/10.1177/0003702817750640.

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The effects exerted by the adsorption of vapors of a non-polar compound (deuterated benzene) and a polar compound (water) on the surface of Ottawa sand and a sample of reservoir sand (Channel), which was previously impregnated with silicon oil or two kinds of surfactants, (2-hydroxyethyl) trimethylammonium oleate (HETAO) and (2-hydroxyethyl)trimethylammonium azelate (HETAA), were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and thermogravimetric analysis (TGA). The surface chemistry of the sandstone rocks was elucidated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX). Terminal surface groups such as hydroxyls can strongly adsorb molecules that interact with these surface groups (surfactants), resulting in a wettability change. The wettability change effect suffered by the surface after treating it with surfactants was possible to be detected by the DRIFTS technique, wherein it was observed that the surface became more hydrophobic after being treated with silicon oil and HETAO; the surface became more hydrophilic after treating it with HETAA.

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Zhu, Wenhui, Caiyun Zhang, Yali Chen, and Qiliang Deng. "Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue." Polymers 13, no. 4 (February 13, 2021): 558. http://dx.doi.org/10.3390/polym13040558.

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Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

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Yang, Xiaomei, Guangzhong Yin, Zhiyong Li, Pengfei Wu, Xiaopei Jin, and Qifang Li. "The Preparation and Chemical Structure Analysis of Novel POSS-Based Porous Materials." Materials 12, no. 12 (June 17, 2019): 1954. http://dx.doi.org/10.3390/ma12121954.

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In this work, we reported the preparation and chemical analysis of novel polyhedral oligomeric silsesquioxane (POSS)-based porous materials, which were prepared according to Friedel-Crafts chloromethylation by using aluminum chloride as the catalyst and dichloromethane as the solvent. Through controlling the treatment solvent (water or methanol) and kinds of POSS, several materials with different morphologies were conveniently obtained. The chemical structure of porous materials was systematically characterized by Fourier-transform infrared (FTIR) spectra, 29Si Nuclear Magnetic Resonance (NMR), 13C NMR, and X-ray photoelectron spectroscopy (XPS). The samples were further characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) to study their crystallinity, morphology, and thermal properties, respectively. The work systematically demonstrated the chemical structure of the porous materials. Moreover, the advantages and disadvantages of the preparation method and typical properties of the material were evaluated through a comparative analysis with other related research works.

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Jaleh, Babak, Ehsan Sabzi Etivand, Bahareh Feizi Mohazzab, Mahmoud Nasrollahzadeh, and Rajender S. Varma. "Improving Wettability: Deposition of TiO2 Nanoparticles on the O2 Plasma Activated Polypropylene Membrane." International Journal of Molecular Sciences 20, no. 13 (July 5, 2019): 3309. http://dx.doi.org/10.3390/ijms20133309.

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Radio frequency plasma is one of the means to modify the polymer surface namely in the activation of polypropylene membranes (PPM) with O2 plasma. Activated membranes were deposited with TiO2 nanoparticles by the dip coating method and the bare sample and modified sample (PPM5-TiO2) were irradiated by UV lamps for 20–120 min. Characterization techniques such as X-ray diffraction (XRD), Attenuated total reflection technique- Fourier transform infrared spectroscopy (ATR-FTIR), Thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM) and water contact angle (WCA) measurements were applied to study the alteration of ensuing membrane surface properties which shows the nanoparticles on the sample surface including the presence of Ti on PPM. The WCA decreased from 135° (PPM) to 90° (PPM5-TiO2) and after UV irradiation, the WCA of PPM5-TiO2 diminished from 90° to 40°.

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Liu, Fu Juan, Qiu Na Cui, Ji Huan He, and Dong Dong Fei. "Preparation, Characterization and Ionizing Radiation Protection Properties of Electrospun Nanofibrous Mats Embedded with Erbium Oxide (Er₂O₃) Nanoparticles." Journal of Nano Research 27 (March 2014): 121–27. http://dx.doi.org/10.4028/www.scientific.net/jnanor.27.121.

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Ionizing radiation directly causes serious damage to human health, and a protective system capable of absorbing or reflecting ionizing radiation is required urgently. In this work, electrospun poly (vinyl alcohol) (PVA) and Poly (vinyl Alcohol)/Erbium Oxide (PVA/Er2O3) nanocomposite fibrous mats were fabricated. These PVA or PVA/Er2O3 composite nanofibers were completely characterized using scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, Thermogravimetric Analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Furthemore, air permeability and ionizing radiation protection properties of these mats were also measured. Under a certain constant electropinning condition, the PVA or PVA/Er2O3 composite nanofibers showed an excellent morphology. The ionizing radiation protection capability of nanofibrous mats is considerably improved when incorporated with Er2O3 nanoparticles.

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Zhang, Chuang, Long Li, Yuanhang Xin, Jiaqi You, Jing Zhang, Wanlu Fu, and Na Wang. "Development of Trans-1,4-Polyisoprene Shape-Memory Polymer Composites Reinforced with Carbon Nanotubes Modified by Polydopamine." Polymers 14, no. 1 (December 29, 2021): 110. http://dx.doi.org/10.3390/polym14010110.

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In this study, which was inspired by mussel-biomimetic bonding research, carbon nanotubes (CNTs) were interfacially modified with polydopamine (PDA) to prepare a novel nano-filler (CNTs@PDA). The structure and properties of the CNTs@PDA were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The CNTs and the CNTs@PDA were used as nanofillers and melt-blended into trans-1,4 polyisoprene (TPI) to create shape-memory polymer composites. The thermal stability, mechanical properties, and shape-memory properties of the TPI/CNTs and TPI/CNTs@PDA composites were systematically studied. The results demonstrate that these modifications enhanced the interfacial interaction, thermal stability, and mechanical properties of TPI/CNTs@PDA composites while maintaining shape-memory performance.

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Luo, Chunhua, Meijuan Qian, and Qiujing Dong. "Synthesis and characterization of thermosensitive and polarity-sensitive fluorescent PNIPAM-coated gold nanoparticles." e-Polymers 17, no. 1 (January 1, 2017): 65–70. http://dx.doi.org/10.1515/epoly-2016-0247.

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AbstractThermosensitive PNIPAM-coated Au nanoparticles (AuNPs@P(NIPAM-co-MADMAC)) were synthesized by the radical “grafting through” copolymerization of 4-methacryloyloxy-4′-dimethylaminochalcone (MADMAC), MAEL-capped AuNPs and N-isopropylacrylamide (NIPAM) using azobisisobutyronitrile (AIBN) as the initiator. AuNPs@P(NIPAM-co-MADMAC) were characterized by transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), 1H nuclear magnetic resonance (NMR), and Fourier transform infrared (FTIR) spectroscopy. AuNPs@P(NIPAM-co-MADMAC) exhibited thermo-sensitivity from poly(NIPAM-co-MADMAC) chains and sensitive fluorescence from the MADMAC group. AuNPs@P(NIPAM-co-MADMAC) showed weak fluorescence after the temperature increased from 25°C to 45°C, or after β-cyclodextrin (β-CD) was added. Furthermore, it exhibited strong fluorescence when the solvent was changed to ethanol or chloroform.

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Chaitongrat, Buaworn, and Sutichai Chaisitsak. "Novel Preparation and Characterization of Fe₂O₃/CNT Thin Films for Flammable Gas Sensors." Materials Science Forum 947 (March 2019): 47–51. http://dx.doi.org/10.4028/www.scientific.net/msf.947.47.

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In this work, novel preparation for Fe2O3/CNT thin films was investigated. The Fe/CNT thin films were synthesized through vertical floating-catalyst chemical vapor deposition technique (FC-CVD) and subsequently annealed in air. The various annealing temperature to create Fe2O3 was examined and characterized by field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Ultraviolet–visible spectroscopy (UV-Vis) and Raman spectroscopy. In addition, effect of wet/dry process on gas sensing of Fe2O3/CNTs was also investigated. The results suggest that the interfacial oxide layer helps to significantly improve LPG sensing performance with rapid response and recovery times. The proposed method can be considered as a promising approach for producing ultra-Fe2O3/CNT thin films that are appropriate for sensing application.

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López-Saucedo, Felipe, Jesús Eduardo López-Barriguete, Guadalupe Gabriel Flores-Rojas, Sharemy Gómez-Dorantes, and Emilio Bucio. "Polypropylene Graft Poly(methyl methacrylate) Graft Poly(N-vinylimidazole) as a Smart Material for pH-Controlled Drug Delivery." International Journal of Molecular Sciences 23, no. 1 (December 28, 2021): 304. http://dx.doi.org/10.3390/ijms23010304.

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Surface modification of polypropylene (PP) films was achieved using gamma-irradiation-induced grafting to provide an adequate surface capable of carrying glycopeptide antibiotics. The copolymer was obtained following a versatile two-step route; pristine PP was exposed to gamma rays and grafted with methyl methacrylate (MMA), and afterward, the film was grafted with N-vinylimidazole (NVI) by simultaneous irradiation. Characterization included Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and physicochemical analysis of swelling and contact angle. The new material (PP-g-MMA)-g-NVI was loaded with vancomycin to quantify the release by UV-vis spectrophotometry at different pH. The surface of (PP-g-MMA)-g-NVI exhibited pH-responsiveness and moderate hydrophilicity, which are suitable properties for controlled drug release.

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Luo, Wei, Yan Tang, De Gang Ouyang, Bin Han, Ming Hui Li, and Shan He Zhu. "Rapid Solvent-Free Melting Synthesis of Tungsten Nitrides with Lamellar, Solid Spherical Nanostructures at a Low Temperature." Advanced Materials Research 535-537 (June 2012): 314–18. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.314.

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A rapid solvent-free melting route has been successfully developed for the synthesis of tungsten nitrides with lamellar and solid spherical nanostructures which have considerably different surface areas (106.4 m2g-1contrast to 8.3 m2g-1) by the reaction of WCl6 and NaNH2 at 220 °C for 2-5 h directly, and it is found that the heat insulating property of reaction container plays important roles in the composition, phase, and morphologies of the nitrides. The products were analyzed by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). Their thermal stability and surface area were measured by thermogravimetric analysis (TGA) and BET, respectively. Finally, the possible formation mechanism of tungsten nitrides with different morphologies was also investigated.

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Wu, Jun Yan, Fei Chen, Qiang Shen, and Lian Meng Zhang. "Antimony-Doped SnO₂ Nanoparticles with Controlled Doping Level via Nonaqueous Sol-Gel Procedure." Materials Science Forum 745-746 (February 2013): 685–89. http://dx.doi.org/10.4028/www.scientific.net/msf.745-746.685.

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Antimony-doped tin oxide (ATO) nanoparticles with controlled doping level were prepared by a nonaqueous solution route, using alcohol as the solvent, citric acid as an agent, tin (IV) tetrachloride as tin source and antimony (III) chlorideas as antimony sources. As-synthesized samples were characterized by Thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), transmission electron micrographs (TEM), N2 adsorption-desorption isotherms, and X-ray photoelectron spectroscopy (XPS). The results showed that the content of citric acid was the most important processing parameter which was largely governing the reaction course and the complete incorporation of Sb. When the citric acid to metal mol ratio was 2, the particles were the highly crystallized ATO nanoparticles of about 20nm and the Sb atoms were indeed incorporated into the SnO2 crystal structure (cassiterite SnO2).

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Marzec, Anna, Bolesław Szadkowski, Jacek Rogowski, Waldemar Maniukiewicz, Dariusz Moszyński, Przemysław Rybiński, and Marian Zaborski. "Carminic Acid Stabilized with Aluminum-Magnesium Hydroxycarbonate as New Colorant Reducing Flammability of Polymer Composites." Molecules 24, no. 3 (February 3, 2019): 560. http://dx.doi.org/10.3390/molecules24030560.

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In this study, hybrid pigments based on carminic acid (CA) were synthesized and applied in polymer materials. Modification of aluminum-magnesium hydroxycarbonate (LH) with CA transformed the soluble chromophore into an organic-inorganic hybrid colorant. Secondary ion mass spectroscopy (TOF-SIMS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and UV-Vis spectroscopy were used to study the structure, composition, and morphology of the insoluble LH/CA colorant. Successful modification of the LH was confirmed by the presence of interactions between the LH matrix and molecules of CA. XPS analysis corroborated the presence of CA complexes with Mg2+ ions in the LH host. The batochromic shift in UV-Vis spectra of the organic-inorganic hybrid colorant was attributed to metal-dye interactions in the organic-inorganic hybrid colorants. Strong metal-dye interactions may also be responsible for the improved solvent resistance and chromostability of the modified LH. In comparison to uncolored ethylene-norbornene copolymer (EN), a modified EN sample containing LH/CA pigment showed lower heat release rate (HRR) and reduced total heat release (THR), providing the material with enhanced flame retardancy.

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Azharudeen, A. Mohamed, A. Mohamed Ismail Badhusha, Mohd Shahnawaz Khan, S. Arun Prabhu, P. Vijaya Kumar, R. Karthiga, Hamza A. Odeibat, Huma Naz, K. Buvaneswari, and Md Rabiul Islam. "Solar Power Light-Driven Improved Photocatalytic Action of Mg-Doped CuO Nanomaterial Modified with Polyvinylalcohol." Journal of Nanomaterials 2022 (March 14, 2022): 1–15. http://dx.doi.org/10.1155/2022/2430840.

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Sonochemical synthesis was used to create novel solar light active Mg-doped CuO nanoparticles. Through a chemical impregnation method, the produced nanomaterial was changed with PVA (polyvinylalcohol). The optical properties, crystal structure, and surface morphologies of the synthesized nanomaterials were probed by UV-visible spectroscopy (UV-vis-DRS), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL), thermogravimetric analysis (TGA), and BET specific surface area studies. The prepared nanomaterials were utilized for the photocatalytic destruction of methylene blue (MB). The photocatalytic activity of PVA-modified Mg-doped CuO nanocomposite is magnificent to CuO and Mg-doped CuO nanomaterials. This is because of the remarkable electron-hole dissociation and overwhelming increased photocatalytic activity achieved through surface modification. Additionally, the consequence of several reaction factors like pH, catalyst dosage, and MB concentration was deliberated. This research could lead to the development of polymer-based metal oxide-doped catalysts for the decomposition of organic contaminants in wastewater.

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Jang, Jum Suk, Eun Sun Kim, Hyun Gyu Kim, Sang Min Ji, Youngkwon Kim, and Jae Sung Lee. "Nitrogen-doped titanium oxide microrods decorated with titanium oxide nanosheets for visible light photocatalysis." Journal of Materials Research 25, no. 6 (June 2010): 1096–104. http://dx.doi.org/10.1557/jmr.2010.0133.

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Nitrogen-doped titania with a unique two-level hierarchical structure and visible light photocatalytic activity is reported. Thus, nitrogen-doped titanium oxide microrods decorated with N-doped titanium oxide nanosheets were synthesized by a hydrothermal reaction in NH4OH and postcalcination. During the calcination, the in situ incorporation of nitrogen atoms of ammonium ion into titania lattice was accompanied by the structural evolution from titanate to anatase titania. The morphological and structural evolution was monitored by scanning electron microscopy (SEM), x-ray diffraction (XRD), thermogravimetric analysis/differential thermal analysis (TGA/DTA), Raman, Fourier transform infrared (FTIR), x-ray absorption near edge structure (XANES), x-ray photoelectron spectroscopy (XPS), and adsorption isotherms. The N-doping brought visible light absorption, and the material exhibited high photocatalytic activity in the decomposition of Orange II under visible light irradiation (λ ≥ 400 nm), especially when it was loaded with 1 wt% Pt as a cocatalyst.

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Subrati, Mohammed S., Sunil P. Lonkar, and Ahmed A. Abdala. "Amine-Functionalized Graphene for Natural Gas Sweetening." Advanced Materials Research 1064 (December 2014): 21–25. http://dx.doi.org/10.4028/www.scientific.net/amr.1064.21.

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Natural gas is often contaminated with acid gases; commonly hydrogen sulfide (H2S) andcarbon dioxide (CO2). In addition to their offensive odor and high toxicity, acid gases can cause serious corrosion problems in a gas plant due to their acidic nature and may reduce the efficiency of gas treatment processes. Therefore, several natural gas sweetening processes have been developed for the removal of acid gases. In present work, we report the employment of amine-functionalized graphene hybrid for adsorption of acid gases. Graphene was selected as a solid sorbent due to its very high specific surface area and ability to undergo various chemical transformations.Considering high affinity of amines towards H2S, an aminated polymer, polyethylenimine (PEI) was used as a functionalizing agent. The resulting hybrids were characterized using Fourier Transform Infrared spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS), elemental analysis, X-ray Diffraction analysis (XRD), and Thermogravimetric Analysis (TGA). These hybrids are envisioned as materials with high H2S sorption capacities and hold great promise in natural gas sweetening applications.

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32

Poonsawat, Thinnaphat, Thanyaphat Techalertmanee, Peerapong Chumkaeo, Isti Yunita, Titiya Meechai, Montree Namkajorn, Soraya Pornsuwan, and Ekasith Somsook. "Facile Synthesis of High Performance Iron Oxide/Carbon Nanocatalysts Derived from the Calcination of Ferrocenium for the Decomposition of Methylene Blue." Catalysts 9, no. 11 (November 12, 2019): 948. http://dx.doi.org/10.3390/catal9110948.

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Iron oxide/carbon nanocatalysts were successfully synthesized by the calcination of ferrocenium at high temperatures ranging from 500 to 900 °C. Then the synthesized nanocomposites were characterized by XRD (X-Ray Diffraction), TEM (Transmission Electron Microscopy), VSM (Vibrating-Sample Magnetometry), BET (Brunauer-Emmett-Teller surface area measurements), TGA (Thermogravimetric Analysis), XPS (X-Ray Photoelectron Spectroscopy), EPR (Electron Paramagnetic Resonance), and CHN elemental analysis. The prepared nanocatalysts were applied for the decomposition of methylene blue as a model in wastewater treatment. It was unexpected to discover that the prepared nanocatalysts were highly active for the reaction with methylene blue in the dark even though no excess of hydrogen peroxide was added. The nanocatalyst calcined at 800 °C exhibited the rod shape with the best catalytic activity. The nanocatalysts could be reused for 12 times without the significant loss of the catalytic activity.

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Liu, Bo, Chunmei Jiang, Chunling Zhang, Xuetao Bai, and Jianxin Mu. "Octasilsesquioxane-reinforced TMBP epoxy nanocomposites: Characterization of thermal, flame-retardant, and morphological properties." High Performance Polymers 24, no. 8 (September 21, 2012): 747–55. http://dx.doi.org/10.1177/0954008312451477.

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Organic–inorganic nanocomposites comprising epoxy resins and polyhedral oligomeric silsesquioxanes (POSS) were prepared via in situ polymerization of 3,3′,5,5′-tetramethyl-4,4′-biphenyl diglycidyl epoxy resins and 4,4′-diaminodiphenylsulfone. The thermal, fire-retardant, and morphological properties of the nanocomposites were studied using thermogravimetric analysis (TGA), thermogravimetry-Fourier transform infrared (TG-FTIR) spectroscopy, microscale combustion calorimeter (MCC), limiting oxygen index (LOI), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The peak heat release rate and the total heat release were significantly reduced with the incorporation of POSS into the epoxy networks, based on the MCC results. Moreover, the LOI value slightly increased with the increase in POSS content. Further, SEM and XPS were used to explore the char residues of the pure epoxy resin and POSS-containing system. The introduction of POSS was found to lead to the formation of an inert layer on the surface of the materials, which protects the internal structure from decomposition.

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34

Nyamukamba, P., L. Tichagwa, S. Mamphweli, and L. Petrik. "Silver/Carbon Codoped Titanium Dioxide Photocatalyst for Improved Dye Degradation under Visible Light." International Journal of Photoenergy 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/3079276.

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Herein, we report the synthesis of quartz supported TiO2 photocatalysts codoped with carbon and silver through the hydrolysis of titanium tetrachloride followed by calcination at 500°C. The prepared samples were characterized by UV-Vis diffuse reflectance spectroscopy, high resolution scanning electron microscopy (HRSEM), Raman spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Codoping of TiO2 with Ag and carbon resulted in an increase in the surface area of the photocatalyst and altered the ratio of the anatase to rutile phase. The absorption edge of all the doped TiO2 photocatalysts redshifted and the band gap was reduced. The lowest band gap of 1.95 eV was achieved by doping with 0.5% Ag. Doping TiO2 using carbon as the only dopant resulted in a quartz supported photocatalyst that showed greater photocatalytic activity towards methyl orange than undoped TiO2 and also all codoped TiO2 photocatalysts under visible light irradiation.

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35

Jia, Yuan, Hong-Xia Yan, Song Li, and Tianye Liu. "Tribology Property of Benzoxazine–Bismaleimide Composites with Hyperbranched Polysilane-Grafted Multi-Walled Carbon Nanotubes." Nano 11, no. 06 (June 2016): 1650061. http://dx.doi.org/10.1142/s1793292016500612.

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To reveal the wear mechanism of hyperbranched polysilane (HBPSi) grafted multi-walled carbon nanotubes (HBPSi–MWCNTs) modified benzoxazine–bismaleimide (BOZ–BMI) resin (HBPSi–MWCNTs/BOZ–BMI), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) were employed. The results indicated that the suitable addition of HBPSi–MWCNTs could largely enhance the tribological properties of BOZ–BMI composites. The worn surface of the composites showed that the severe wear of the BOZ–BMI resin was converted from adhesive wear to abrasive wear with the addition of HBPSi–MWCNTs. The excellent tribological properties can be attributed to the improved interfacial adhesion between HBPSi–MWCNTs and the BOZ–BMI resin matrix. The TGA demonstrated that the composite with 0.8[Formula: see text]wt.% HBPSi–MWCNTs exhibits better thermal resistance; thus, it can inhibit adhesive wear during the friction process. The XPS spectra and the surface energy showed that the HBPSi–MWCNTs could be exposed on the worn surface of the composite to improve the anti-wear capacity of the composites further.

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Yu, Tao, Changqing Hu, and Yan Li. "Functionalization of Graphene and Its Influence on Mechanical Properties and Flame Retardancy of Jute/Poly(lactic acid) Composite." Journal of Nanoscience and Nanotechnology 19, no. 11 (November 1, 2019): 7074–82. http://dx.doi.org/10.1166/jnn.2019.16659.

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In this work, 9,10-dihydro-9-oxa-phosphaphenanthrene-10-oxide (DOPO) was covalently grafted onto the surface of graphene to get modified graphene (G-DOPO) firstly. The mechanical properties and flame retardancy of jute/poly(lactic acid) (PLA) composite with G-DOPO were studied. According to Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), it was confirmed that DOPO was grafted on the surface of graphene successfully. Thermogravimetric analysis (TGA) results demonstrated that the residue char of the composites increased with the addition of G-DOPO. The total heat release (THR) of the composite was significantly reduced and the limiting oxygen index (LOI) increased after adding G-DOPO into the composite. Moreover, the mechanical properties results showed that the comprehensive effects of G-DOPO on the interface enhancement and matrix toughness were found.

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37

Kim, Sang Kyum, Ji Yun Park, Soon Choel Hwang, Do Kyun Lee, Sang Heon Lee, Moon Hee Han, and Young Woo Rhee. "Radiolytic Preparation of Electrocatalysts with Pt-Co and Pt-Sn Nanoparticles for a Proton Exchange Membrane Fuel Cell." Journal of Nanomaterials 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/960379.

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Nanosized Pt-Sn/VC and Pt-Co/VC electrocatalysts were prepared by a one-step radiation-induced reduction (30 kGy) process using distilled water as the solvent and Vulcan XC72 as the supporting material. While the Pt-Co/VC electrodes were compared with Pt/VC (40 wt%, HiSpec 4000), in terms of their electrocatalytic activity towards the oxidation of H2, the Pt-Co/VC electrodes were evaluated in terms of their activity towards the hydrogen oxidation reaction (HOR) and compared with Pt/VC (40 wt%, HiSpec 4000), Pt-Co/VC, and Pt-Sn/VC in a single cell. Additionally, the prepared electrocatalyst samples (Pt-Co/VC and Pt-Sn/VC) were characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical surface area (ECSA), and fuel cell polarization performance.

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38

Wu, Fangyi, Xiaohui Bao, and Jiangbo Wang. "One-Step Reduction of Graphene Oxide with Phosphorus/Silicon-Containing Compound and Its Flame Retardancy in Epoxy Resin." Polymers 13, no. 22 (November 18, 2021): 3985. http://dx.doi.org/10.3390/polym13223985.

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A novel graphene-based phosphorus/silicon-containing flame retardant (GO-DOPO-V) was obtained via one-step reduction of graphene oxide (GO) with phosphorus/silicon-containing compound (DOPO-V). The Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectrometer (XPS), Atomic force microscope (AFM) and Thermogravimetric analysis (TGA) measurements were used to confirm the structure and morphology. After incorporation of 2 wt% GO-DOPO-V, the maximum decreases of 28.8% in peak heat release rate and 15.6% in total heat release are achieved compared to that of pure epoxy resin (EP). Furthermore, TGA and Scanning electron microscopy (SEM) measurement showed that GO-DOPO-V significantly enhanced the thermal stability and residual char strength of EP. Thus, attributed to the barrier effect of GO and phosphorus/silicon layer formation by DOPO-V, GO-DOPO-V was a high-efficient flame retardant to improve the combustion behavior of EP nanocomposite.

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Lee, Yu-Jin, Da-Jung Chung, Sang-Hyub Oh, and Seong-Ho Choi. "Introduction of Bifunctional Group onto MWNT by Radiation-Induced Graft Polymerization and Its Use as Biosensor-Supporting Materials." Journal of Nanomaterials 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/127613.

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A biosensor comprisingtyrosinaseimmobilized on bifunctionalized multiwalled carbon nanotube (MWNT) supports was prepared for the detection of phenolic compounds in drinks such as red wine and juices. The MWNT supports were prepared by radiation-induced graft polymerization (RIGP) of epoxy-containing glycidyl methacrylate (GMA), to covalently immobilize thetyrosinase, and vinyl ferrocene (VF), which can act as an electron transfer mediator via redox reactions. The bifunctionalized MWNTs were characterized by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). Electrodes prepared with the MWNTs showed increased current with increasing VF content. A biosensor comprisingtyrosinaseimmobilized on the bifunctionalized MWNTs could detect phenol at 0.1–20 mM. Phenolics in red wine and juices were determined using the biosensor after its calibration.

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Ma, Kaixuan, Qiu Wang, Qianyun Rong, Dapeng Zhang, Shihai Cui, and Jing Yang. "Preparation of magnetic carbon/Fe3O4 supported zero-valent iron composites and their application in Pb(II) removal from aqueous solutions." Water Science and Technology 76, no. 10 (July 28, 2017): 2680–89. http://dx.doi.org/10.2166/wst.2017.384.

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Abstract Nanoscale zero-valent iron (NZVI) was first assembled on magnetic carbon/Fe3O4 (CM) with a combination of hydrothermal and liquid phase reduction methods. The novel NZVI@CM magnetic nanocomposites have the merits of large surface area, unique magnetic property, low cost and environmental friendliness. They can be used for Pb(II) removal in aqueous solution. The materials were characterized by using transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS) and Brunauer–Emmett–Teller (BET) adsorption. The various parameters, such as reaction time, dosage of catalyst, solution pH and acid ions concentrations were studied. The removal efficiency of Pb(II) can be obviously increased by the combination of appropriate CM and NZVI. The removal efficiency of Pb(II) is 99.7% by using 60 mg of NZVI@CM at pH 7. The kinetics study indicates that the Pb(II) removal accords to pseudo-second-order kinetics model.

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Wang, Songlin, Fei Wang, Zongjia Song, Xiaoming Song, Xuxu Yang, and Qian Wang. "Preparation of cellulose nanocrystals using highly recyclable organic acid treated softwood pulp." BioResources 14, no. 4 (October 10, 2019): 9331–51. http://dx.doi.org/10.15376/biores.14.4.9331-9351.

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Cellulose nanocrystals (CNC) were successfully obtained from softwood pulp by p-toluenesulfonic acid (p-TsOH) hydrolysis under the treatment of p-TsOH mass concentration of 60%, temperature of 70 °C, reaction time of 4 h, and pulp to solution ratio of 1:20 (g / mL). Zeta potential and dynamic light scattering (DLS), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA) were used to characterize the physical-chemical properties of the CNC. Under these conditions, the CNC exhibited good thermal stability in the suspension with a high crystallinity index of 90.1%. The CNC had an average diameter of 4.87 nm and average length 175.5 nm with no undesired elemental contamination. The degradation temperature of the CNC was relatively high at 310 °C. Moreover, p-TsOH was recovered by crystallization technology, and the recovery rate was over 70%, providing an environmentally friendly way for the development of biomass materials.

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Aguado-Deblas, Laura, Rafael Estevez, Marco Russo, Valeria La Parola, Felipa M. Bautista, and Maria Luisa Testa. "Microwave-Assisted Glycerol Etherification Over Sulfonic Acid Catalysts." Materials 13, no. 7 (March 30, 2020): 1584. http://dx.doi.org/10.3390/ma13071584.

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Glycerol is the main by-product of biodiesel production. For this reason, its valorization into value-added products, by using green procedures, represents an important goal. Different sulfonic acid silica- or titania-based catalysts were prepared, characterized and tested in the glycerol etherification process, assisted by microwaves, in order to obtain biodiesel additives. The surface and structural properties of the catalysts were investigated by means of N2 adsorption isotherms, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and acid capacity measurements by X-Ray Fluorescence Spectroscopy (XRF). The best performance in terms of activity was achieved in the presence of the sulfonic function directly linked to the amorphous silica. By the correlation of the structure properties of the materials and their activity, the performance of the catalysts was shown to be influenced mainly by the surface area, pore volume and acidity. Recycling experiments performed over the most active systems showed that the sulfonic silica-based materials maintained their performance during several cycles.

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Elimbinzi, Elianaso, Stephen S. Nyandoro, Egid B. Mubofu, Amin Osatiashtiani, Jinesh C. Manayil, Mark A. Isaacs, Adam F. Lee, and Karen Wilson. "Synthesis of Amine Functionalized Mesoporous Silicas Templated by Castor Oil for Transesterification." MRS Advances 3, no. 38 (2018): 2261–69. http://dx.doi.org/10.1557/adv.2018.347.

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ABSTRACTMesoporous silicas were synthesized via a surfactant-templated sol-gel route using castor oil as the templating agent under acidic medium. The resulting silicas were subsequently amine functionalized with 3-aminopropyltriethoxysilane (NH2-MTS), [3-(2-aminoethylamino)-propyl]trimethoxysilane (NN-MTS), and [3-(diethylamino)propyl]trimethoxysilane(DN-MTS) to introduce surface basicity. Surface physicochemical properties were characterized by field emission gun scanning electron microscopy (FEGSEM), nitrogen porosimetry, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and diffuse reflectance infrared fourier transform spectroscopy (DRIFTS). As-synthesised materials exhibit type IV adsorption-desorption isotherms characteristic of mesoporous structures. Clusters of spherical shaped materials were observed by FEGSEM, suggesting growth of silica occurs within colloidal dispersions. High-resolution N 1s XP spectra and DRIFT spectra confirmed the presence of amine groups in the organo-amine functionalised mesoporous silicas. The amine functionalised mesoporous silicas were active for the transesterification of tributyrin with methanol, with conversion found to increase from NH2-MTS< NN-MTS< DN-MTS.

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Wang, Jiangbo. "Flame Retardancy and Dispersion of Functionalized Carbon Nanotubes in Thiol-Ene Nanocomposites." Polymers 13, no. 19 (September 28, 2021): 3308. http://dx.doi.org/10.3390/polym13193308.

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A polysilicone flame retardant (PA) was synthesized and covalently grafted onto the surface of carbon nanotubes (CNTs) via amide linkages to obtain modified CNTs (CNTs-PA). The grafting reaction was characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectrometer (XPS), Transmission electron microscopy (TEM) and Thermogravimetric analysis (TGA), and the resultant CNTs-PA was soluble and stable in polar solvents Chloroform. Thiol-ene (TE)/CNTs-PA nanocomposites were prepared via Ultraviolet curing. The flame retardancy of thiol-ene nanocomposites was improved, especially for the heat release rate. Moreover, the results from Scanning electron microscopy (SEM) and Dynamic mechanical thermal analysis (DMTA) showed that the CNTs-PA improved the dispersion of CNTs in thiol-ene and enhanced the interfacial interaction between CNTs-PA and thiol-ene matrix.

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PANDEY, J. K., M. H. KIM, D. M. CHUN, C. S. LEE, and S. H. AHN. "SURFACE MODIFICATION OF POLYETHYLENE (PE) BY THE DEPOSITION OF TITANIUM DIOXIDE (TiO2) NANOPARTICLES TO ENHANCE THE PHOTOCATALYTIC ACTIVITIES." Surface Review and Letters 16, no. 02 (April 2009): 259–63. http://dx.doi.org/10.1142/s0218625x09012561.

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In recent years, there has been growing interest in the preparation of TiO 2-deposited materials for the application in different fields of photocatalytic activities, such as photocatalysis, dye-sensitized solar cells, antireflective coatings, and electro-chromic devices. TiO 2 particles were deposited on the PE surface by spraying method at room temperature. The deposition analysis was conducted by atomic force microscopy (AFM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FE-SEM) for monitoring the variation in morphology and different properties. It was found that the surface was deposited uniformly with higher concentration of particles and did not affect the inherent properties of polymers. The deposited TiO 2 particles favor the photodegradation of synthetic nonbiodegradable polymeric materials, which will ultimately decompose in the environment.

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Hu, Chunlian, Wei Zhang, Yuantao Chen, Na Ye, DaWa YangJi, Haizhe Jia, Yanting Shen, and Minna Song. "Adsorption of Co(II) from aqueous solution using municipal sludge biochar modified by HNO3." Water Science and Technology 84, no. 1 (May 24, 2021): 251–61. http://dx.doi.org/10.2166/wst.2021.199.

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Abstract Here adsorption studies were proposed on a carboxylated sludge biochar (CSB) material modified by HNO3 to assess its capacity in the removal of cobalt from aqueous solution. The as-prepared sludge biochar material was characterized by Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), energy-dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The isotherm process could be well described by the Langmuir isotherm model. The adsorption kinetics indicated that cobalt adsorption followed a pseudo-second-order kinetics model. The mechanism between Co(II) and biochar involved electrostatic interaction, ion exchange, surface complexation and physical function. The adsorption capacity on CSB was as high as 72.27 mg·g−1, surpassing original sludge biochar (SB) as CSB had abundant oxygen-containing functional groups and many hydroxyls, plus the BET surface areas increased when SB was modified by HNO3, which stimulated adsorption effect. Therefore, this work shows that CSB could be used as an efficient adsorbent to remove Co(II) in wastewater.

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Bekhoukh, Amina, Imane Moulefera, Lilia Sabantina, and Abdelghani Benyoucef. "Development, Investigation, and Comparative Study of the Effects of Various Metal Oxides on Optical Electrochemical Properties Using a Doped PANI Matrix." Polymers 13, no. 19 (September 29, 2021): 3344. http://dx.doi.org/10.3390/polym13193344.

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A comparative study was performed in order to analyze the effect of metal oxide (MO) on the properties of a polymeric matrix. In this study, polyaniline (PANI)@Al2O3, PANI@TiC, and PANI@TiO2 nanocomposites were synthesized using in situ polymerization with ammonium persulfate as an oxidant. The prepared materials were characterized by various analytical methods such as X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV/visible (UV/Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). Furthermore, the conductive properties of the materials were tested using the four-point probe method. The presence of MO in the final product was confirmed by XPS, XRD, FTIR, and TEM, while spectroscopic characterization revealed interactions between the MOs and PANI. The results showed that the thermal stability was improved when the MO was incorporated into the polymeric matrix. Moreover, the results revealed that incorporating TiO2 into the PANI matrix improves the optical bandgap of the nanocomposite and decreases electrical conductivity compared to other conducting materials. Furthermore, the electrochemical properties of the hybrid nanocomposites were tested by cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD). The obtained results suggest that the PANI@TiO2 nanocomposite could be a promising electrode material candidate for high-performance supercapacitor applications.

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48

Cruz-Benítez, María Montserrat, Pablo Gónzalez-Morones, Ernesto Hernández-Hernández, José Roberto Villagómez-Ibarra, Javier Castro-Rosas, Esmeralda Rangel-Vargas, Heidi Andrea Fonseca-Florido, and Carlos Alberto Gómez-Aldapa. "Covalent Functionalization of Graphene Oxide with Fructose, Starch, and Micro-Cellulose by Sonochemistry." Polymers 13, no. 4 (February 4, 2021): 490. http://dx.doi.org/10.3390/polym13040490.

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In this work, we report the synthesis of graphene oxide (GO) nanohybrids with starch, fructose, and micro-cellulose molecules by sonication in an aqueous medium at 90 °C and a short reaction time (30 min). The final product was washed with solvents to extract the nanohybrids and separate them from the organic molecules not grafted onto the GO surface. Nanohybrids were chemically characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy and analyzed by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). These results indicate that the ultrasound energy promoted a chemical reaction between GO and the organic molecules in a short time (30 min). The chemical characterization of these nanohybrids confirms their covalent bond, obtaining a grafting percentage above 40% the weight in these nanohybrids. This hybridization creates nanometric and millimetric nanohybrid particles. In addition, the grafted organic molecules can be crystallized on GO films. Interference in the ultrasound waves of starch hybrids is due to the increase in viscosity, leading to a partial hybridization of GO with starch.

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49

Xu, Bo, Wen Ma, Lushan Shao, Lijun Qian, and Yong Qiu. "Enhancement of an organic–metallic hybrid charring agent on flame retardancy of ethylene-vinyl acetate copolymer." Royal Society Open Science 6, no. 3 (March 2019): 181413. http://dx.doi.org/10.1098/rsos.181413.

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An organic triazine charring agent hybrid with zinc oxide (OTCA@ZnO) was prepared and well characterized through Fourier transform infrared spectrometry (FTIR), solid-state nuclear magnetic resonance (SSNMR), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The flame retardancy and thermal behaviour of intumescent flame retardant ethylene-vinyl acetate (EVA) composites combining OTCA@ZnO and ammonium polyphosphate (APP) were investigated using limited oxygen index (LOI), UL-94 vertical burning, cone calorimetry and TGA. The structure and morphology of chars were investigated by scanning electron microscopy (SEM), FTIR, laser Raman spectroscopy analysis (LRS) and X-ray photoelectron spectroscopy (XPS). Results revealed that OTCA@ZnO exhibited excellent thermal stability and dispersity after hybridization. The flame retardancy and smoke suppression properties of EVA were significantly improved by introducing APP/OTCA@ZnO. TGA results indicated that APP/OTCA@ZnO presented an excellent synergistic effect and promoted the char formation of EVA composites. Residue analysis results showed more char with high quality connected by richer P–O–C, P–N and P–O–Si structures was formed in APP/OTCA@ZnO system than APP/HOTCA/ZnO system, which consequently suppressed more efficiently the combustion and smoke production due to the in situ catalytic carbonization effect of hybrid.

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50

Andrade-Guel, M., C. Cabello-Alvarado, V. Cruz-Delgado, P. Bartolo-Perez, P. De León-Martínez, A. Sáenz-Galindo, G. Cadenas-Pliego, and C. Ávila-Orta. "Surface Modification of Graphene Nanoplatelets by Organic Acids and Ultrasonic Radiation for Enhance Uremic Toxins Adsorption." Materials 12, no. 5 (March 1, 2019): 715. http://dx.doi.org/10.3390/ma12050715.

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Ultrasound energy is a green and economically viable alternative to conventional techniques for surface modification of materials. The main benefits of this technique are the decrease of processing time and the amount of energy used. In this work, graphene nanoplatelets were treated with organic acids under ultrasonic radiation of 350 W at different times (30 and 60 min) aiming to modify their surface with functional acid groups and to improve the adsorption of uremic toxins. The modified graphene nanoplatelets were characterized by Fourier transform infrared spectroscopy (FT–IR), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The optimum time for modification with organic acids was 30 min. The modified nanoplatelets were tested as adsorbent material for uremic toxins using the equilibrium isotherms where the adsorption isotherm of urea was adjusted for the Langmuir model. From the solution, 75% of uremic toxins were removed and absorbed by the modified nanoplatelets.

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Journal articles on the topic 'Thermogravimetric analysis (TGA), viscoelasticity, x-ray photoelectron spectroscopy (XPS)'

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