Journal articles: 'Carbon deposition resistance'

1

Shi, Yu, Shiwei Wang, Yiming Li, Fan Yang, Hongbo Yu, Yuting Chu, Tong Li, and Hongfeng Yin. "Improving Anti-Coking Properties of Ni/Al2O3 Catalysts via Synergistic Effect of Metallic Nickel and Nickel Phosphides in Dry Methane Reforming." Materials 15, no. 9 (April 22, 2022): 3044. http://dx.doi.org/10.3390/ma15093044.

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A series of NiP-x/Al2O3 catalysts containing different ratio of metallic nickel to nickel phosphides, prepared by varying Ni/P molar ratio of 4, 3, 2 through a co-impregnation method, were employed to investigate the synergistic effect of metallic nickel-nickel phosphides in dry methane reforming reaction. The Ni/Al2O3 catalyst indicates good activity along with severe carbon deposition. The presence of phosphorus increases nickel dispersion as well as the interaction between nickel and alumina support, which results in smaller nickel particles. The co-existence of metallic nickel and nickel phosphides species is confirmed at all the P contained catalysts. Due to the relative stronger CO2 dissociation ability, the NiP-x/Al2O3 catalysts indicate obvious higher resistance of carbon deposition. Furthermore, because of good balance between CH4 dissociation and CO2 dissociation, NiP-2/Al2O3 catalyst exhibits best resistance of carbon deposition, few carbon depositions were formed after 50 h of dry methane reforming.

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Qingliang, Shen, Li Hejun, Zhao Fengling, Song Qiang, and Fu Qiangang. "Electrophoretic deposition of carbon nanotubes for improved ablation resistance of carbon/carbon composites." Corrosion Science 132 (March 2018): 204–13. http://dx.doi.org/10.1016/j.corsci.2018.01.001.

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Tanaka, Kazuto, Takanobu Nishikawa, Kazuhiro Aoto, and Tsutao Katayama. "Effect of Carbon Nanotube Deposition Time to the Surface of Carbon Fibres on Flexural Strength of Resistance Welded Carbon Fibre Reinforced Thermoplastics Using Carbon Nanotube Grafted Carbon Fibre as Heating Element." Journal of Composites Science 3, no. 1 (January 12, 2019): 9. http://dx.doi.org/10.3390/jcs3010009.

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In recent years, carbon fibre reinforced thermoplastics (CFRTP) are expected to be used as lightweight structural materials for mass-produced vehicles. CFRTP with thermoplastics as matrix allows us to weld them using melting of matrix by heating. We have been developing a direct resistance heating method, which uses carbon fibres as the resistance heating element. Carbon nanotube (CNT) is expected to be used as additive to FRP and we reported that the fibre/matrix interfacial shear strength was improved by grafting CNT on the surface of carbon fibres and tensile lap-shear strength was improved by using CNT grafted carbon fibre as the heating element for welding. For the practical use of CFRTP for structural parts, flexural strength is also necessary to be evaluated. In this study, flexural test was carried out to clarify the effect of CNT deposition time to the surface of carbon fibres on flexural strength of resistance welded CFRTP using CNT grafted carbon fibre as the heating element. The highest flexural strength was obtained when CNT10, for which CNT is grafted on the carbon fibres for deposition time of 10 min, was used for the heating element of resistance welding. In the case of CNT deposition time of 60 min, the lowest flexural strength was obtained because of the poor impregnation of the resin into the carbon fibre due to the excess CNT on the carbon fibres.

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Xu, Xian Feng, Ling Sheng Zeng, Tian Ouyang, and Ling Zhi Chai. "Carbon Felt Properties of Pyrolytic Carbon Felt Direct Thermal CVD." Materials Science Forum 852 (April 2016): 1371–75. http://dx.doi.org/10.4028/www.scientific.net/msf.852.1371.

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Taking acetylene as the carbon source gas diluted with nitrogen gas in this paper, carbon felt was heated under the nitrogen atmosphere, the temperature of carbon felt increased using heat generated by itself, which so as to cleave the carbon source gas and densify carbon felt by pyrolytic carbon deposition. The electrothermal property of carbon felt at elevated temperature and pyrolytic carbon was fabricated by direct thermal chemical vapor deposition (CVD) were investigated. Deposition rate and microstructure morphology of pyrolytic carbon in the carbon felt under different processes were also researched by scanning electron microscopy (SEM). The results show that: the resistivity of carbon felt decreases with increasing temperature at 100°C~1000°C, temperature coefficient of resistance is-4.067×10-4. Deposition and Growth of Pyrolytic carbon are by small microcrystalline and layer mode, respectively, with the extension of the deposition time, tree-ring shape is formed. When other conditions are the same, the higher of gas carbon concentration, the faster of pyrolytic carbon deposition rate.

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Bannov, Alexander G., Ondřej Jašek, Jan Prášek, Jiří Buršík, and Lenka Zajíčková. "Enhanced Ammonia Adsorption on Directly Deposited Nanofibrous Carbon Films." Journal of Sensors 2018 (September 17, 2018): 1–14. http://dx.doi.org/10.1155/2018/7497619.

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The ammonia adsorption on the nanostructured carbon thin film was significantly influenced by the choice of deposition temperature and deposition time of thin film synthesis. The thin films were prepared on Si/SiO2 substrates by chemical vapour deposition in Ar/C2H2 gas mixture using iron catalytic nanoparticles. The analysis of the grown layer by the scanning and transmission electron microscopy showed the transition from long multiwalled nanotubes (MWCNTs) to bamboo-like hollow carbon nanofiber structure with the decrease of the deposition temperature from 700 to 600°C. Further, the material was analyzed by energy-dispersive X-ray spectroscopy and Raman spectroscopy confirmed the transition from graphitic sp2 structure to highly defective structure at lower deposition temperature. The resistance of the prepared layer strongly depends on deposition temperature (Td) and deposition time (td). High resistance layer, 38.6 kΩ, was formed at Td 600°C and td 10 min, while at Td 700°C and td 60 min, the resistance decreased to 860 ohms. Such behaviour is consistent with MWCNTs being responsible for the formation of the conductive network. Such system was studied using chemiresistor ammonia gas sensor configuration. The sensor resistance increased when exposed to ammonia in all the cases, but their response varied considerably. A decrease in deposition time, from 60 to 10 min, and the deposition temperature, from 700 to 600°C, led to the 10-fold increase in the sensor response. The measurements carried out at room temperature showed the higher sensor response than the measurements carried out at 200°C. This behaviour can be explained by the change in adsorption-desorption equilibrium at different temperatures. Analysis of dependence of the sensor response on the ammonia concentration proved that the underlying resistance change mechanism is chemisorption of ammonia molecules on the carbon network corresponding to the Langmuir isotherm.

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Chae, Hyang Hoon, Bo-Hye Kim, Kap Seung Yang, and Hee-Gweon Woo. "Boric Oxide Deposition on Carbon Nanofibers for Oxidation Resistance." Journal of Nanoscience and Nanotechnology 13, no. 8 (August 1, 2013): 5645–48. http://dx.doi.org/10.1166/jnn.2013.7065.

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Kalenik, Jerzy, Konrad Kielbasinski, Piotr Firek, Elżbieta Czerwosz, and Jan Szmidt. "Thermal properties of modified carbon films." Circuit World 42, no. 1 (February 1, 2016): 37–41. http://dx.doi.org/10.1108/cw-10-2015-0055.

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Purpose – The purpose of this paper is to present thermal properties of palladium-carbon films prepared by physical vapour deposition (PVD)/chemical vapour deposition (CVD) methods. Design/methodology/approach – Thin palladium-carbon films were prepared at Tele- and Radioresearch Institute. Test structures containing palladium-carbon films and titanium electrodes were made. Temperature-resistance characteristics were measured. Findings – The results show strong temperature dependence of modified carbon film resistance. The dependence is stable, and so modified carbon films can be applied for various electronic applications. Originality/value – The paper presents thermal properties of thin palladium-carbon prepared by original PVD/CVD method at Tele- and Radioresearch Institute.

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Zeng, Yan, Ayano Kimura, Peipei Zhang, Jiaming Liang, Jiaqi Fan, Liwei Xiao, Chengwei Wang, Guohui Yang, Xiaobo Peng, and Noritatsu Tsubaki. "Resistance against Carbon Deposition via Controlling Spatial Distance of Catalytic Components in Methane Dehydroaromatization." Catalysts 11, no. 2 (January 21, 2021): 148. http://dx.doi.org/10.3390/catal11020148.

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Molybdenum-zeolite catalysts always suffer from severe carbon deposition and rapid deactivation in the methane dehydroaromatization (MDA) process. Herein, we present a strategy that controls spatial distance between Mo species and HMCM-22 zeolite over Mo/HMCM-22 catalysts, to inhibit the severe carbon deposition. Our characterization analyses demonstrate that the Mo/HMCM-22 catalysts possess the same active components, but the spatial distance plays a key role in determining product selectivity in the MDA process. The MDA performance reveals that Mo/HMCM-22-MM (mechanical milling) catalyst, with a medium spatial distance between Mo species and HMCM-22 zeolite, significantly inhibits carbon deposition and produces high selectivity to benzene. This work shows that spatial distance between molybdenum and zeolite is an important property for suppressing carbon deposition and improving benzene selectivity in MDA process.

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LU, J. W., W. L. WANG, K. J. LIAO, and B. Y. WAN. "STRAIN-INDUCED RESISTANCE CHANGES OF CARBON NANOTUBE FILMS." International Journal of Modern Physics B 19, no. 01n03 (January 30, 2005): 627–29. http://dx.doi.org/10.1142/s0217979205029183.

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The strain-induced resistance changes of both SWNT and MWNT films have been studied. Carbon nanotubes in this study were synthesized by hot filament chemical vapor deposition. Experimental results showed that there is a striking piezoresistive effect in carbon nanotube films. The relative change in resistance of carbon nanotube films was increased with the increasing strain. In the same strain, the resistance changes of SWNT films exceed that of MWNT films. The origin of the resistance change in the films may be caused by strain-induced change in the bandgap and intertube contact resistance.

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Hannula, Pyry-Mikko, Minttu Junnila, Dawid Janas, Jari Aromaa, Olof Forsén, and Mari Lundström. "Carbon Nanotube Fiber Pretreatments for Electrodeposition of Copper." Advances in Materials Science and Engineering 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/3071913.

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There is increasing interest towards developing carbon nanotube-copper (CNT-Cu) composites due to potentially improved properties. Carbon nanotube macroscopic materials typically exhibit high resistivity, low electrochemical reactivity, and the presence of impurities, which impede its use as a substrate for electrochemical deposition of metals. In this research, different CNT fiber pretreatment methods, such as heat treatment, immersion in Watts bath, anodization, and exposure to boric acid (H3BO3), were investigated to improve the electrochemical response for copper deposition. It was shown that these treatments affect the surface activity of CNTs, including electrical resistivity, polarization resistance, and active surface area, which influence the electrodeposition process of copper. Properties of CNT structures and CNT-Cu composites were researched by electrochemical impedance spectroscopy (EIS), galvanostatic copper deposition, scanning electron microscope (SEM), and four-point electrical resistance measurements. Heat treatment, Watts bath, anodization, and boric acid treatments were shown to be effective for modifying the CNT surface reactivity for subsequent electrochemical deposition of copper.

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11

Tang, De Weng, Tong Chun Kuang, and Rui Lan Zhao. "Effects of Deposit Time on Combustion Flame Deposition of Carbon Coatings on the Surface of Cemented Carbide." Advanced Materials Research 873 (December 2013): 384–90. http://dx.doi.org/10.4028/www.scientific.net/amr.873.384.

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At present, most of the researches on carbide surface modification are focused on the method of chemical vapor deposition and physical vapor deposition in order to enhance its wear resistance and surface hardness. In this paper, C2H2 and O2 of flame are used to deposit carbon coatings on YG 16 cemented carbide surface. The influence of deposition time have been investigated with the method of XRD, SEM. Carbon coatings structure, quality and Cross sectional microstructures of carbon coating was analyzed.The experimental result show that after different deposition time, the typical spherical diamond\nanometer carbon tube and diamond-graphite-no crystal carbon coatings have been formed on the surface of cemented carbide.

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12

Lee, Sang Heon. "Electronic Properties Carbon Film Using Chemical Process." Solid State Phenomena 124-126 (June 2007): 251–54. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.251.

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Electro-deposition of carbon film on silicon substrate in methanol solution was carried out with various current density, solution temperature and electrode spacing between anode and cathode. The carbon films with smooth surface morphology and high electrical resistance were formed when the distance between electrode was relatively wider. The electrical resistance of the carbon films were independent of both current density and solution temperature.

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Nikolenko, S. V., S. N. Khimukhin, and P. S. Gordienko. "Alumo Matrix Composite Materials for Electro Spark Deposition on Carbon Steel." Solid State Phenomena 316 (April 2021): 745–51. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.745.

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The article presents the research results on the problem of the influence of the electric spark discharge parameters and electrode alloys, based on metal matrix materials, used for electro spark deposition (ESD) on the physicochemical and operational characteristics of the coating layer. Experimental dependences of the cathode weight gain, erosion resistance of the anode materials, mass transfer coefficient, wear resistance of the coating, and their mathematical expressions with a reliability criterion of at least R2> 0.9044, are obtained. It is established that, after steel 45 sample has been treated by ESD with metal-matrix materials, the hardness of its surface increases 6 times on the average and the wear resistance – 2 times. The best values of wear resistance at all the modes under investigation have been obtained for the anode material NiO-Zr-TiO2-Al. Data series of cathode weight gain (ƩΔc), erosion resistance of anode materials (ƩΔа), mass transfer coefficient Кmt, coating wear resistance after ESD (Ʃcwr), coating formation efficiency (γcfe), ESD energy efficiency (γeef), are also obtained. These data can be recommended for achieving the required parameters of the ESD on steels using metal-matrix materials.

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Rannik, Ü., P. Keronen, I. Mammarella, and T. Vesala. "Vertical advection and nocturnal deposition of ozone over a boreal pine forest." Atmospheric Chemistry and Physics Discussions 8, no. 5 (October 23, 2008): 18437–55. http://dx.doi.org/10.5194/acpd-8-18437-2008.

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Abstract. Night-time ozone deposition for a Scots pine forest in Southern Finland was studied at the SMEAR II measurement station by evaluating the turbulent eddy covariance (EC), storage change and vertical advection fluxes. Similarly to night-time carbon dioxide flux, the eddy-covariance flux of ozone was decreasing with turbulence intensity (friction velocity), and storage change of the compound did not compensate the reduction (well-known night-time measurement problem). Accounting for vertical advection resulted in invariance of ozone deposition rate on turbulence intensity. This was also demonstrated for carbon dioxide, verified by independent measurements of NEE by chamber systems. The result highlights the importance of advection when considering the exchange measurements of any scalar. Analysis of aerodynamic and laminar boundary layer resistances by the model approach indicated that the surface resistance and/or chemical sink strength was limiting ozone deposition. The possible aerial ozone sink by known fast chemical reactions with sesquiterpenes and NO explain only a minor fraction of ozone sink. Thus the deposition is controlled either by stomatal uptake or surface reactions or both of them, the mechanisms not affected by turbulence intensity. Therefore invariance of deposition flux on turbulence intensity is expected also from resistance and chemical sink analysis.

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Rannik, Ü., I. Mammarella, P. Keronen, and T. Vesala. "Vertical advection and nocturnal deposition of ozone over a boreal pine forest." Atmospheric Chemistry and Physics 9, no. 6 (March 23, 2009): 2089–95. http://dx.doi.org/10.5194/acp-9-2089-2009.

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Abstract. Night-time ozone deposition for a Scots pine forest in Southern Finland was studied at the SMEAR II measurement station by evaluating the turbulent eddy covariance (EC), storage change and vertical advection fluxes. Similarly to night-time carbon dioxide flux, the eddy-covariance flux of ozone was decreasing with turbulence intensity (friction velocity), and storage change of the compound did not compensate the reduction (well-known night-time measurement problem). Accounting for vertical advection resulted in invariance of ozone deposition rate on turbulence intensity. This was also demonstrated for carbon dioxide, verified by independent measurements of NEE by chamber systems. The result highlights the importance of advection when considering the exchange measurements of any scalar. Analysis of aerodynamic and laminar boundary layer resistances by the model approach indicated that the surface resistance and/or chemical sink strength was limiting ozone deposition. The possible aerial ozone sink by known fast chemical reactions with sesquiterpenes and NO explain only a minor fraction of ozone sink. Thus the deposition is controlled either by stomatal uptake or surface reactions or both of them, the mechanisms not affected by turbulence intensity. Therefore invariance of deposition flux on turbulence intensity is expected also from resistance and chemical sink analysis.

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Zhou, Lei, Jian Feng Huang, Li Yun Cao, He Jun Li, Wei Hao, and Hai Bo Ouyang. "Influence of Pulse Frequency on the Structure and Oxidation Resistance of AlPO₄ Ceramics Coating and its Deposition Dynamics." Materials Science Forum 852 (April 2016): 1095–101. http://dx.doi.org/10.4028/www.scientific.net/msf.852.1095.

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A facile pulse arc discharge deposition method was developed to prepare AlPO4 oxidation resistant outer coating on SiC pre-coated carbon/carbon composites (SiC-C/C). The deposition dynamics and the influence of pulse frequency on composition, microstructure and oxidation resistance of the as-prepared coating were investigated. Results show that pulse arc discharge deposition is an effective route to achieve dense and crack-free AlPO4 coatings. The deposition activation energy of the AlPO4 coating is calculated to be 3.07 kJ·mol-1. The AlPO4 coating prepared at a pulse frequency of 2000 Hz exhibits good oxidation resistance, which can effectively protect C/C composites from oxidation in air at 1773 K for 262 h with a weight loss of 1.58%.

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Yu, Yong Peng. "Preparation, Purification and Properties of Carbon Nanotubes." Advanced Materials Research 557-559 (July 2012): 472–77. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.472.

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At present, CNTs can be a variety of methods in the system, including arc discharge, chemical vapor deposition and laser evaporation method, which arc discharge and chemical vapor deposition method is used in two wider. No matter what kind of prepared CNTs, not high purity, containing the catalyst particles or amorphous carbon particles, graphite particles and other impurities. These impurities mixed with CNTs, it is difficult to meet the research and application needs of CNTs, and thus the study of CNTs purification is necessary. CNTs are made of carbon atoms to SP2 hybrid-based, mixed with SP3 hybrid built into the ideal structure, it can be seen as a sheet of graphene rolled into a cylinder. Therefore inevitable graphite excellent intrinsic properties: such as heat transfer, electrical conductivity, heat resistance, corrosion resistance, thermal shock resistance, lubricity, and biocompatibility, such as a series of excellent performance. In conclusion, CNTs unique structure gives superior performance and broad application prospects

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Pierpaoli, Mattia, Mirosław Sawczak, and Anna Dettlaff. "Development of Microstructured Carbon Coatings by Substrate-Catalytic CVD." Coatings 11, no. 11 (November 18, 2021): 1403. http://dx.doi.org/10.3390/coatings11111403.

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Carbon nanostructured films were synthesized by chemical vapor deposition (CVD) on H18 stainless steel (AISI 440C) sheets with an H2/CH4/N2 gas mixture at various substrate temperatures. During the synthesis, the iron and chromium oxide layer was formed between the steel and carbonaceous layer. The carbon films exhibited wall-like and spherical morphologies and structures, as characterized by scanning electron microscopy and Raman spectroscopy. It was found that the synthesis temperature affects the microsphere density and, therefore, also in the electrochemical behavior. The electrochemical behavior of nanostructured carbon coatings strongly depends on the CVD deposition conditions. The best corrosion resistance (Rp = 11.8 MΩ·cm2, Icorr = 4.4 nA·cm−2) exhibits a nanostructured carbon sample with a moderate amount of sp2-C-rich carbon microspheres CμSs synthesized at 700 °C. The corrosion resistance of the nanostructured carbon coating is better than raw stainless steel.

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Sun, Jie, Ting Liang, Zhuang Zhou Ji, Rui Yan, and Jin Hong Meng. "Corrosion Resistance of Ternary Ni-Cu-P Coatings Prepared by Electroless Method on Carbon Steel." Advanced Materials Research 160-162 (November 2010): 479–83. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.479.

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Ni-Cu-P coatings were prepared by electroless deposition method on carbon steel. The pH value and concentrations of cupric sulfate were studied to character the deposition rate, corrosion resistance of Ni-Cu-P coatings in 3.5% NaCl solution. From the results, it was shown that the deposition rate of Ni-Cu-P coatings increased with the increasing of pH value. The deposition rate speeds up until the deposition rate keeps stable when the pH value is about 8.0-9.0. When pH value was 7.5, the coatings showed good corrosion resistance. In the same conditions of solution compositions and technological conditions, the concentration of cupric sulfate must be lower than 2g/L if the copper and nickel altogether co-deposited. The minimal corrosion current and excellent surface state for the coatings can be obtained when the concentration of cupric sulfate was about 0.8 g/L.

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Beard, J. D., S. Aleksandrov, C. H. Walker, D. Wolverson, J. M. Mitchels, and S. N. Gordeev. "Magnetically enhanced plasma coating of nanostructures with ultrathin diamond-like carbon films." RSC Adv. 4, no. 51 (2014): 26635–44. http://dx.doi.org/10.1039/c4ra02841d.

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Zhang, Xu, Hui Xing Zhang, Xiang Ying Wu, and Tong He Zhang. "Low Stress Tetrahedral Amorphous Carbon Films Prepared by Filtered Vacuum Arc Deposition." Materials Science Forum 475-479 (January 2005): 3623–26. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.3623.

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The tetrahedral amorphous carbon films are attracting materials because of their properties similar to diamond, such as high hardness, resistivity, optical transparency, chemical inertness and low coefficient of friction. These properties make it ideal for wear resistance application on cutting tools, automotive component, aerospace components and orthopedic prosthesis etc. In this paper the structures, mechanical properties and wear resistance of the tetrahedral amorphous carbon films deposited on silicon under lower pulse bias voltage by filtered catholic vacuum arc deposition system have been investigated. The high quality tetrahedral amorphous carbon film has been obtained. The hardness and elastic modulus of the low stress tetrahedral amorphous carbon films are higher than 60Gpa and 380Gpa respectively determined by nano indentation tests. The friction performance of the tetrahedral amorphous carbon films was also studied by SRV tests, the results show: the tetrahedral amorphous carbon films have much lower wear rate than that of silicon substrate.

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Jabbar, Abdul, Ghulam Yasin, Waheed Qamar Khan, M. Yousaf Anwar, Rashid Mustafa Korai, Muhammad Naeem Nizam, and Ghulam Muhyodin. "Electrochemical deposition of nickel graphene composite coatings: effect of deposition temperature on its surface morphology and corrosion resistance." RSC Advances 7, no. 49 (2017): 31100–31109. http://dx.doi.org/10.1039/c6ra28755g.

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The present work describes the fabrication of Ni–graphene composite coatings on carbon steel at different deposition temperatures (15 °C, 30 °C, 45 °C and 60 °C, respectively) by an electrochemical codeposition method.

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Liu, Jia, Jian Feng Huang, Li Yun Cao, and Yu Xin. "ZrSiO₄/SiC Oxidation Protective Coating for Carbon/Carbon Composites Prepared by Hydrothermal Electrophoretic Deposition." Key Engineering Materials 512-515 (June 2012): 1070–73. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.1070.

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In order to improve the oxidation resistance of carbon/carbon (C/C) composites, a ZrSiO4coating on SiC pre-coated C/C composites was prepared by a hydrothermal electrophoretic deposition process. The phase composition, surface and cross-section microstructure, anti-oxidation property of the as-prepared ZrSiO4/SiC coating was investigated. Results show that hydrothermal electrophoretic deposition is an effective route to achieve crack-free ZrSiO4 outer coatings. The ZrSiO4/SiC coating can protect C/C composites from oxidation at 1773 K for 332 h with a weigh loss rate of only 4.83×10-5g/cm2·h.

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Guo, Junling, Shupeng Zhao, He Yang, Fengxiang Zhang, and Jinping Liu. "Electron regulation enabled selective lithium deposition for stable anodes of lithium-metal batteries." Journal of Materials Chemistry A 7, no. 5 (2019): 2184–91. http://dx.doi.org/10.1039/c8ta11193f.

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An SEI wrapped tubular carbon array architecture is developed to allow electron transport from the current collector to the inner tubular carbon without passing through the high-resistance SEI. Therefore, lithium plating occurs mainly inside the tubular carbon, suppressing the dendrite growth.

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Danes, Cristiana-Alexandra, Cristina Dumitriu, Sorin Vizireanu, Bogdan Bita, Ioana-Maria Nicola, Gheorghe Dinescu, and Cristian Pirvu. "Influence of Carbon Nanowalls Interlayer on Copper Deposition." Coatings 11, no. 11 (November 16, 2021): 1395. http://dx.doi.org/10.3390/coatings11111395.

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This research deals with the deposition of copper on a steel substrate. Two different methods were investigated: electrochemical and magnetron sputtering. The deposition parameters were optimized to obtain a coating layer with uniform granular structure and good adhesion to the substrate. As a novelty, carbon nanowalls (CNW) were used as reinforcement in copper coatings on the steel surface. The morphology of the coatings, adhesion and Vickers microhardness were performed to emphasize the CNW influence on the coating properties. Open circuit potential and Tafel analysis were used for electrochemical characterization. These kinds of CNW-copper composite with improved hardness and adhesion and surface electrical resistance around 1 Ω·cm could have miscellaneous applications in different domains such as aerospace, electronics, automotive and power-generation.

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Lyu, Linghui, Yunxing Han, Qingxiang Ma, Shengene Makpal, Jian Sun, Xinhua Gao, Jianli Zhang, Hui Fan, and Tian-Sheng Zhao. "Fabrication of Ni-Based Bimodal Porous Catalyst for Dry Reforming of Methane." Catalysts 10, no. 10 (October 20, 2020): 1220. http://dx.doi.org/10.3390/catal10101220.

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Dry reforming of methane (DRM) can effectively convert two greenhouse gases into high-valued chemicals, in which the syngas produced by the reaction can be directly used as raw gases for Fischer–Tropsch synthesis and methanol synthesis. Ni-based catalysts for the DRM reaction with comparable initial activity to noble metals are the focus of most researchers, but their poor carbon deposition resistance easily causes their low stability. More importantly, the nickel loading will affect the catalytic activity and carbon deposition resistance of the catalyst. Herein, a series of Ni/Al2O3 catalysts with bimodal pores was prepared and characterized by X-ray diffraction (XRD), N2 physical adsorption–desorption, H2-temperature programmed reduction (H2-TPR), temperature programmed hydrogenation (TPH), Raman, and thermogravimetric analysis (TG). The results show that the interesting bimodal structure catalysts could provide a high surface area and contribute to the mass transfer. Besides, the catalytic performance of the DRM reaction is sensitive to nickel loadings. In this study, the Ni/Al2O3 catalyst with nickel loadings of 6% and 8% exhibited excellent catalytic activity and carbon deposition resistance. These findings will provide a new strategy to design a highly efficient and stable heterogeneous catalyst for industry.

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Meng, Junguang, Xiaobo Wang, Zengli Zhao, Xianshuang Wu, Anqing Zheng, Guoqiang Wei, Zhen Huang, and Haibin Li. "A highly carbon-resistant olivine thermally fused with metallic nickel catalyst for steam reforming of biomass tar model compound." RSC Advances 7, no. 62 (2017): 39160–71. http://dx.doi.org/10.1039/c7ra06219b.

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Denisov, L. V., A. G. Boytsov, and M. V. Siluyanova. "Providing of Operational Properties for Gas-Turbine Engine Parts and Assemblies Using Electrospark Deposition." Materials Science Forum 992 (May 2020): 574–79. http://dx.doi.org/10.4028/www.scientific.net/msf.992.574.

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Article explains manufacturing capability of titanium parts reliability enhancement and life cycle enhancement by electrospark deposition using low energy discharges. Carbon electrodes used to form functional properties of parts surface layer. Alloyed carbooxide zone consist of highly dispersed structure (with particles of titanium carbide, titanium oxide, graphite), with 3-10 micron thick, and high hardness antifrictionality. Alloyed layer contain ordered phase Ti8C5, TiC, and the structure of Ti6C3,75. Parts dimensions almost do not changed after electrospark deposition with carbon electrodes. Subsequent diamond burnishing decrease friction coefficient and surface roughness. Fatigue resistance increased after healing of defects and microcracks. Local carbooxidation and burnishing used to increase wear resistance of titanium alloys.

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Łamacz, Agata. "Toluene Steam Reforming over Ni/CeZrO2—The Influence of Steam to Carbon Ratio and Contact Time on the Catalyst Performance and Carbon Deposition." Catalysts 12, no. 2 (February 15, 2022): 219. http://dx.doi.org/10.3390/catal12020219.

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The formation of tars during coal or biomass gasification is a serious issue resulting in decreasing efficiency of the process and increased maintenance costs. The decomposition of tars can be conducted via catalytic steam reforming that enriches the produced gas in hydrogen. Nevertheless, the catalyst should be characterized by high activity, stability, and resistance towards carbon deposition. Ceria-zirconia supported nickel (Ni/CeZrO2) is a very good candidate to catalyze tar removal—Ni is an active phase for reforming reactions, while CeZrO2 provides the active sites that play important roles in protecting the catalyst from carbon deposition. Ni/CeZrO2 shows high activity in the steam reforming of model tar compounds. In this paper, its performance in the steam reforming of toluene and carbon deposition is discussed considering the changing parameters of the reaction: the temperature, steam to carbon ratio, and the contact time.

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Mikuš, Rastislav, Ivan Kováč, and Jozef Žarnovský. "Effect of Microstructure on Properties of NiCrBSi Alloys Applied by Flame-Powder Deposition." Advanced Materials Research 1059 (December 2014): 1–9. http://dx.doi.org/10.4028/www.scientific.net/amr.1059.1.

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This article deals with studying the relationships among the chemical composition, microstructure and properties (hardness, micro-hardness, wear resistance) of powder additives based on NiCrBSi after their deposition. Tested materials reached a relatively wide range of hardness after deposition, which corresponds to their chemical composition and microstructure. The abrasive wear resistance of materials was tested on an emery cloth. The results indicate that both the hardness and abrasive wear resistance of tested materials depend especially on the content of carbon and chromium. Microstructural analysis indicates that the structure of tested materials is formed by the γ-Ni solid solution and intermediate phases based on boron, silicon and carbon. Those mostly form eutectics (three types), or are excluded by precipitation. There was also found a significant effect of chromium, but especially carbon content on the ratio between the solid solution and eutectics in the microstructure of tested materials. These different ratios of solid solution and eutectics were markedly reflected in micro-hardness behaviours in deposited layers. Micro-hardness values confirmed also the presence of carbidic particles in the layers with carbon content higher than 0.7 wt%.

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Li, Xiaodong, and Bharat Bhushan. "Micro/nanomechanical and tribological characterization of ultrathin amorphous carbon coatings." Journal of Materials Research 14, no. 6 (June 1999): 2328–37. http://dx.doi.org/10.1557/jmr.1999.0309.

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Micro/nanomechanical and tribological characterization of ultrathin amorphous carbon coatings, deposited by filtered cathodic arc (FCA), direct ion beam (IB), electron cyclotron resonance plasma chemical vapor deposition (ECR-CVD), and sputter (SP) deposition processes on Si substrate have been conducted using a nanoindenter with a nanoscratch attachment and an accelerated ball-on-flat tribometer. Coating thicknesses of 20, 10, 5 nm and, for the first time, 3.5 nm coatings have been investigated. It was found the FCA coating exhibits the highest hardness and elastic modulus, followed by the ECR-CVD, IB, and SP coatings. In general, the thicker coatings exhibited better scratch/wear performance than the thinner coatings due to their better load-carrying capacity as compared to the thinner coatings. At 20 nm, the FCA and ECR-CVD coatings show the best scratch and wear resistance, while the IB and ECR-CVD coatings show the best scratch and wear resistance at 10 nm. Five nanometer thick coatings show reasonable scratch and wear resistance, while 3.5 nm thick coatings show extremely low load-carrying capacity and poor scratch and wear resistance. It appears that the 3.5 nm coatings studied are unfeasible for scratch and wear resistance applications as of now.

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Li, Fei, Jingyu Sun, Hualong Xie, Kun Yang, and Xiaofei Zhao. "Thermal Deformation of PA66/Carbon Powder Composite Made with Fused Deposition Modeling." Materials 13, no. 3 (January 22, 2020): 519. http://dx.doi.org/10.3390/ma13030519.

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Polyamide 66 (PA66) is a material with high wear resistance, toughness, and heat resistance. However, low stiffness and thermal deformation during thermal processes define applications in many conditions. Carbon powder efficiently enhances stiffness and reduces thermal deformation, which makes up defects of plastic materials. However, forming a composite with fused deposition modeling (FDM) that accumulates material to a specified location by melting plastic filaments is limited, including fluidity and viscosity to form normally. In this paper, filaments of polyamide 66 (PA66) reinforced with carbon powder were produced. Digimat was used to analyze the composite material properties of different carbon contents and predict the proper carbon content. Then, the material properties were imported to ANSYS software to simulate the thermal deformation of the workpieces during processing. It was verified that adding carbon powder is helpful in decreasing thermal deformation. Comparing experiments and simulations, we found that 20% carbon mass fraction was best, and that thermal deformation was minimal at 240 °C nozzle temperature while hot bed temperature was 90 °C. The optimal ratio of extrusion speed to filling speed was 0.87, and the best aspect ratio was 0.25.

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Yu, Ning, Masahiro Nakajima, Qing Shi, Zhan Yang, Huaping Wang, Lining Sun, Qiang Huang, and Toshio Fukuda. "Characterization of the Resistance and Force of a Carbon Nanotube/Metal Side Contact by Nanomanipulation." Scanning 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/5910734.

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A high contact resistance restricts the application of carbon nanotubes (CNTs) in fabrication of field-effect transistors (FETs). Thus, it is important to decrease the contact resistance and investigate the critical influence factors such as the contact length and contact force. This study uses nanomanipulation to characterize both the resistance and the force at a CNT/Au side-contact interface inside a scanning electron microscopy (SEM). Two-terminal CNT manipulation methods, and models for calculating the resistance and force at contact area, are proposed to guide the measurement experiments of a total resistance and a cantilever’s elastic deformation. The experimental results suggest that the contact resistance of CNT/Au interface is large (189.5 kΩ) when the van der Waals force (282.1 nN) dominates the contact force at the interface. Electron-beam-induced deposition (EBID) is then carried out to decrease the contact resistance. After depositing seven EBID points, the resistance is decreased to 7.5 kΩ, and the force increases to 1339.8 nN at least. The resistance and force at the contact area where CNT was fixed exhibit a negative exponential correlation before and after EBID. The good agreement of this correlation with previous reports validates the proposed robotic system and methods for characterizing the contact resistance and force.

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Tawfiq, Thaier Abid, Abdulsatta Mohammedr Jassim, and Haitham A. Alani. "Study the Influence of CNTs Deposited by Laser on the Surface of Al 2024 Alloy." Defect and Diffusion Forum 418 (August 19, 2022): 67–78. http://dx.doi.org/10.4028/p-9ns9k0.

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Laser powder deposition (LPD) has been relied on to improve the surface properties of materials. Nowadays, an excellent reinforcement for aluminum and aluminum alloys could be carbon nanotubes (CNTs). The surface of aluminum alloy 2024 (Al Cu4Mg1) is coated with double-walled and multiwalled carbon nanotubes (DWCNTs, MWCNTs) using laser preplaced powder deposition with pulsed Nd:YAG to evaluate its effect on enhancing hardness and corrosion resistance. The laser power, pulse duration, scanning speed, and frequency, were controlled to complete this task. Since the best DWCNT deposited layer was obtained at the optimal process conditions, the Vickers micro-hardness and corrosion resistance of the coated Al 2024 surface improved in the readouts. The results showed that DWCNT improved specific essential surface attributes, namely hardness, abrasive wear resistance, and corrosion resistance, more than MWCNTs, according to the findings. Although MWCNTs have less penetration, their dispersion on the surface is superior to DWCNTs.

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Vander Wal, Randy, and Mpila Makiesse Nkiawete. "Carbons as Catalysts in Thermo-Catalytic Hydrocarbon Decomposition: A Review." C — Journal of Carbon Research 6, no. 2 (April 14, 2020): 23. http://dx.doi.org/10.3390/c6020023.

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Thermo-catalytic decomposition is well-suited for the generation of hydrogen from natural gas. In a decarbonization process for fossil fuel—pre-combustion—solid carbon is produced, with potential commercial uses including energy storage. Metal catalysts have the disadvantages of coking and deactivation, whereas carbon materials as catalysts offer resistance to deactivation and poisoning. Many forms of carbon have been tested with varied characterization techniques providing insights into the catalyzed carbon deposition. The breadth of studies testing carbon materials motivated this review. Thermocatalytic decomposition (TCD) rates and active duration vary widely across carbons tested. Regeneration remains rarely investigated but does appear necessary in a cyclic TCD–partial oxidation sequence. Presently, studies making fundamental connections between active sites and deposit nanostructures are few.

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36

Yun, Jaeyong, Min-Sung Bae, Jin Su Baek, Tae Wan Kim, Sung-Jin Kim, and Jung-Hyuk Koh. "Modeling of Optimized Lattice Mismatch by Carbon-Dioxide Laser Annealing on (In, Ga) Co-Doped ZnO Multi-Deposition Thin Films Introducing Designed Bottom Layers." Nanomaterials 13, no. 1 (December 22, 2022): 45. http://dx.doi.org/10.3390/nano13010045.

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In this study, modeling of optimized lattice mismatch by carbon-dioxide annealing on (In, Ga) co-doped ZnO multi-deposition thin films was investigated with crystallography and optical analysis. (In, Ga) co-doped ZnO multi-deposition thin films with various types of bottom layers were fabricated on sapphire substrates by solution synthesis, the spin coating process, and carbon-dioxide laser irradiation with post annealing. (In, Ga) co-doped ZnO multi-deposition thin films with Ga-doped ZnO as the bottom layer showed the lowest mismatch ratio between the substrate and the bottom layer of the film. The carbon-dioxide laser annealing process can improve electrical properties by reducing lattice mismatch. After applying the carbon-dioxide laser annealing process to the (In, Ga) co-doped ZnO multi-deposition thin films with Ga-doped ZnO as the bottom layer, an optimized sheet resistance of 34.5 kΩ/sq and a high transparency rate of nearly 90% in the visible light wavelength region were obtained.

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37

Jonnalagadda, K. N., and I. Chasiotis. "Strength and Fracture Resistance of Amorphous Diamond-Like Carbon Films for MEMS." Journal of Nanomaterials 2009 (2009): 1–8. http://dx.doi.org/10.1155/2009/204281.

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The mechanical strength and mixed mode I/II fracture toughness of hydrogen-free tetrahedral amorphous diamond-like carbon (ta-C) films, grown by pulsed laser deposition, are discussed in connection to material flaws and its microstructure. The failure properties of ta-C were obtained from films with thicknesses 0.5–3 μm and specimen widths 10–20 μm. The smallest test samples with 10 μm gage section averaged a strength of 7.3±1.2 GPa, while the strength of 20-μm specimens with thicknesses 0.5–3 μm varied between 2.2–5.7 GPa. The scaling of the mechanical strength with specimen thickness and dimensions was owed to deposition-induced surface flaws, and, only in the smallest specimens, RIE patterning generated specimen sidewall flaws. The mode I fracture toughness of ta-C films isKIc=4.4±0.4 MPam, while the results from mixed mode I/II fracture experiments with cracks arbitrarily oriented in the plane of the film compared very well with theoretical predictions.

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38

Voleský, Lukáš, Totka Bakalova, Karolína Borůvková, and Petr Louda. "The Impact of the Deposition Parameters on the Mechanical Properties of Thin Carbon Layers." Defect and Diffusion Forum 368 (July 2016): 95–98. http://dx.doi.org/10.4028/www.scientific.net/ddf.368.95.

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The article describes the effect of the pressure in the chamber during the deposition of thin layers on the basic mechanical properties of thin layers based on carbon. Monitoring parameters are mainly nanohardness, coefficient of friction and adhesion between the layer and substrate. This parameters are observed using nanohardness tester and scratch tester. All observed layers had the same thickens of layers. Carbon layers generally have poor adhesion to the substrate. To improve the adhesion, is used the interlayer of titanium which is between the substrate and carbon layer. Carbon layers are mostly used for their very good sliding properties especially in cases where can not be used process fluids or where is necessary to reduce the friction between the two materials. The carbon layer can also be used in medicine (for their biocompatibility), for machine tools (for their hardness and abrasion resistance) or as barriers layers (for their high chemical resistance).

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39

Golubeva, Elizaveta V., Anna A. Chlenova, Elena A. Stepanova, and Galina V. Kurlyandskaya. "Magnetic properties and giant magnetoimpedance of surface modified Co-based amorphous ribbons with carbon covering." EPJ Web of Conferences 185 (2018): 10001. http://dx.doi.org/10.1051/epjconf/201818510001.

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Fe3Co66Cr3Si16B12 and Fe6Co60Ni10Si14B10 amorphous ribbons were surface modified in toluene at room temperature. Such a treatment resulted in deposition of thin carbon-based layer. As a result of the carbon covering deposition the stress distribution in the near-surface layers was changed due to partial compensation of the initial quenching stresses. Comparative analysis of magnetic and magnetoimpedance properties of as-quenched and surface modified ribbons confirms changes in effective magnetic anisotropy as a result of surface treatment. An increase of the corrosion resistance of the ribbons with carbon covering can be useful for the development amorphous ribbon based magnetic biosensor.

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40

Awang Shri, D. N., J. Ramli, N. A. Alang, and M. M. Mahat. "Effect of Surface Pretreatment on Morphology and Microhardness on Carbon Coating Using PVD." Advanced Materials Research 472-475 (February 2012): 50–54. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.50.

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Alumina (Al2O3) cutting tools have been coated with carbon coating using physical vapor deposition (PVD) to improve its wear resistance. The cutting tools were subjected to surface pretreatments namely blasting and acid etching to improve the coating adhesion onto the substrates. The effects of pretreatments on the cutting tools topography prior to deposition were investigated using atomic force microscopy (AFM) while the surface morphology was investigated using scanning electron microscopy (SEM). The adhesion strength of the carbon coating was investigated using microscratch. This study shows that although the coating were deposited evenly on the surface, the cutting tool that was blasted prior to deposition has better adhesion strength when compared to acid etching and no-pretreatment.

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41

Commodo, Mario, Gianluigi De Falco, Ettore Sarnelli, Marcello Campajola, Alberto Aloisio, Andrea D’Anna, and Patrizia Minutolo. "Resistive Switching Phenomenon Observed in Self-Assembled Films of Flame-Formed Carbon-TiO2 Nanoparticles." Materials 14, no. 16 (August 19, 2021): 4672. http://dx.doi.org/10.3390/ma14164672.

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Nanostructured films of carbon and TiO2 nanoparticles have been produced by means of a simple two-step procedure based on flame synthesis and thermophoretic deposition. At first, a granular carbon film is produced on silicon substrates by the self-assembling of thermophoretically sampled carbon nanoparticles (CNPs) with diameters of the order of 15 nm. Then, the composite film is obtained by the subsequent thermophoretic deposition of smaller TiO2 nanoparticles (diameters of the order of 2.5 nm), which deposit on the surface and intercalate between the carbon grains by diffusion within the pores. A bipolar resistive switching behavior is observed in the composite film of CNP-TiO2. A pinched hysteresis loop is measured with SET and RESET between low resistance and high resistance states occurring for the electric field of 1.35 × 104 V/cm and 1.5 × 104 V/cm, respectively. CNP-TiO2 film produced by flame synthesis is initially in the low resistive state and it does not require an electroforming step. The resistance switching phenomenon is attributed to the formation/rupture of conductive filaments through space charge mechanism in the TiO2 nanoparticles, which facilitate/hinder the electrical conduction between carbon grains. Our findings demonstrate that films made of flame-formed CNP-TiO2 nanoparticles are promising candidates for resistive switching components.

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42

Shi, Anhong, Xin Yang, Cunqian Fang, Yuanqi Weng, Xiao Luo, Ze Zhang, and Qizhong Huang. "Surface Optimization of ZrC–SiC Inner Layer to Enhance Ablation Property of SiC/ZrC–SiC Multi-Layer Coating for C/C Composites." Coatings 11, no. 4 (March 25, 2021): 378. http://dx.doi.org/10.3390/coatings11040378.

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A ZrC–SiC inner layer was fabricated on carbon/carbon composites by pack cementation at different temperatures, aiming to prepare a transition layer for subsequent deposition of SiC and ZrC–SiC layer by chemical vapor deposition and plasma spray. Results show that the structure and phase composition of the inner layer significantly affected the interface bonding strength and thermal shock resistance of the multilayer, which played a vital role in resisting ablation. The jagged and porous surface of the inner layer led to forming a root-like pinning interface, generating a sawtooth combination between the layers. Moreover, the inner layer with high SiC content decreased the coefficient of thermal expansion mismatch between the inner and outer layers. Therefore, the enhanced ablation resistance of the optimum coating was attributed to the improved interface bonding strength and thermal shock resistance caused by the ZrC–SiC inner layer with rough and porous surface structure.

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43

Feng, Z., M. A. Brewer, K. Komvopoulos, I. G. Brown, and D. B. Bogy. "Diamond nucleation on unscratched silicon substrates coated with various non-diamond carbon films by microwave plasma-enhanced chemical vapor deposition." Journal of Materials Research 10, no. 1 (January 1995): 165–74. http://dx.doi.org/10.1557/jmr.1995.0165.

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The efficacy of various non-diamond carbon films as precursors for diamond nucleation on unscratched silicon substrates was investigated with a conventional microwave plasma-enhanced chemical vapor deposition system. Silicon substrates were partially coated with various carbonaceous substances such as clusters consisting of a mixture of C60 and C70, evaporated films of carbon and pure C70, and hard carbon produced by a vacuum are deposition technique. For comparison, diamond nucleation on silicon substrates coated with submicrometer-sized diamond particles and uncoated smooth silicon surfaces was also examined under similar conditions. Except for evaporated carbon films, significantly higher diamond nucleation densities were obtained by subjecting the carbon-coated substrates to a low-temperature high-methane concentration hydrogen plasma treatment prior to diamond nucleation. The highest nucleation density (∼3 × 108 cm−2) was obtained with hard carbon films. Scanning electron microscopy and Raman spectroscopy demonstrated that the diamond nucleation density increased with the film thickness and etching resistance. The higher diamond nucleation density obtained with the vacuum are-deposited carbon films may be attributed to the inherent high etching resistance, presumably resulting from the high content of sp3 atomic bonds. Microscopy observations suggested that diamond nucleation in the presence of non-diamond carbon deposits resulted from carbon layers generated under the pretreatment conditions.

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44

Long, Jin Ming, Xiu Zhang, and He Zhong Pei. "Effect of Triethanolamine Addition in Alkaline Bath on the Electroplating Behavior, Composition and Corrosion Resistance of Zn-Ni Alloy Coatings." Advanced Materials Research 738 (August 2013): 87–91. http://dx.doi.org/10.4028/www.scientific.net/amr.738.87.

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Zn-Ni alloy coatings were electrodeposited on low carbon steel substrate using a cyanide-free alkaline bath containing tetraethylenepentamine (TEPA) and triethanolamine (TEA) as complexing agents for Ni2+cations. Effect of TEA/Ni2+molar ratio on electrodeposition behavior, micromophology, Ni content and corrosion resistance of coatings were studied by means of SEM/EDS, polarization curve and electrochemical impedance spectroscopy (EIS), respectively. It was found that the deposition potential and elecctrochemical impedance of the cathode sample during the electrodeposition was influenced by the TEA/Ni2+molar ratio (TNmr) in the bath. The deposition potential shifts negatively and the impedance rises with increasing TNmrup to 2. The nickel content in Zn-Ni deposit was varied in a range from 16.81 to 19.04 wt.%. The dependence of cathodic current efficiency and depositing velocity of the coating on TNmrof plating bath were also determined. A fine-grained and smooth-faced coating was obtained at TNmr=2, which exhibited the highest corrosion resistance in 3.5% NaCl environment.

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45

Serino, Gianpaolo, Mattia Gusmini, Alberto Luigi Audenino, Giovanni Bergamasco, Ornella Ieropoli, and Cristina Bignardi. "Multiscale Characterization of Isotropic Pyrolytic Carbon Used for Mechanical Heart Valve Production." Processes 9, no. 2 (February 12, 2021): 338. http://dx.doi.org/10.3390/pr9020338.

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Usage of pyrolytic carbon (PyC) to produce mechanical heart valves (MHVs) has led to heart valve replacement being a very successful procedure. Thus, the mechanical properties of employed materials for MHV production are fundamental to obtain the required characteristics of biocompatibility and wear resistance. In this study, two deposition methods of PyC were compared through a multiscale approach, performing three-point bending tests and nanoindentation tests. Adopted deposition processes produced materials that were slightly different. Significant differences were found at the characteristic scale lengths of the deposited layers. Setting changes of the deposition process permitted obtaining PyC characterized by a more uniform microstructure, conferring to the bulk material superior mechanical properties.

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46

Toikka, Andrei S., and Natalia V. Kamanina. "The control of ITO conductive coating relief via laser-oriented deposited carbon nanotubes." Image Journal of Advanced Materials and Technologies 7, no. 1 (2022): 058–67. http://dx.doi.org/10.17277/jamt.2022.01.pp.058-067.

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The paper presents the analysis of the surface relief of ITO conductive layers structured with single-walled carbon nanotubes. The deposition of ITO films and carbon nanotubes was carried out by laser-oriented method using a CO2 laser. The optical scheme was matched to the control electric grid; the strength of the electric field was varied in the range of 100–600 Vcm–1. To analyze the surface, atomic force microscopy in the contact mode and measurement of the wetting angle by sessile drop method was used. Roughness of pure ITO was about 1.8 nm, while in laser-vacuum deposition of carbon nanotubes, roughness varied from 6.4 nm to 22.1 nm with an increase in the electric field during deposition. The relationship between roughness and surface area of coatings and the wetting angle was considered. An increase in the wetting angle from 101.8 degrees, in the case of pure ITO, to 115.0-128.6 degrees, with the deposition of carbon nanotubes, was shown. The results obtained indicate an improvement in the resistance of ITO coatings to moisture during the deposition of carbon nanotubes, which makes it possible to expand their operating conditions and scope in optical electronics, laser and display technology.

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47

Xia, Xin, Glenn Jones, Misbah Sarwar, Qian Tang, Ian Harkness, and David Thompsett. "A DFT study of Pt layer deposition on catalyst supports of titanium oxide, nitride and carbide." Journal of Materials Chemistry A 3, no. 48 (2015): 24504–11. http://dx.doi.org/10.1039/c5ta05904f.

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Due to carbon corrosion under the electrochemical conditions in PEMFCs, alternative ceramic supports to carbon such as TiO₂ have been considered to improve the environmental resistance and catalyst durability.

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48

Wang, She-Guan, Xin-De Bai, Bao-Chu Wang, and Yu-Dian Fan. "The positive roles of metallic droplets in deposition of alloy films by cathodic arc plasma deposition." Journal of Materials Research 11, no. 5 (May 1996): 1137–43. http://dx.doi.org/10.1557/jmr.1996.0146.

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The roles of metallic droplets, which generated from the cathodic arc spot holes in the technology of Cathodic Arc Plasma Deposition (CAPD), are investigated by SEM, TEM, image analysis apparatus, and electronic probe energy spectrum analysis. The results show that though many papers in recent years are devoted to eliminate them, the metallic droplets, including the macrodroplets, have many important positive roles in the preparation of alloy films: they are the main factor to transfer the original composition of alloy cathodic target to the alloy thick films; they preserve the high deposition rate of CAPD to form the basic characteristics of the microstructure and to affect the pore ratios of the films; they also preserve the high melting point elements in the alloy films, and therefore preserve the corrosion resistance of the alloy in the films. The macrodroplets can be eliminated by raising the substrate temperature properly, which is permitted in some cases, such as depositing alloy films onto middle carbon steel as an anticorrosion system, etc.

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OUYANG, RUIZHUO, WEIWEI LI, YANG YANG, WANGYAO ZHANG, KAI FENG, TIANYU ZONG, YARUI AN, SHUANG ZHOU, and YUQING MIAO. "MORPHOLOGY EFFECT OF Ni–Ag/CARBON NANOMATERIALS ON THEIR ELECTROCATALYTIC ACTIVITY FOR GLUCOSE OXIDATION." Surface Review and Letters 23, no. 06 (November 17, 2016): 1650059. http://dx.doi.org/10.1142/s0218625x16500591.

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We presented here three carbon-nanomaterials-based modified glassy carbon electrodes (GCE) with Ni–Ag nanohybrid nanoparticles (NPs) deposited upon, including single-wall carbon nanotubes (SWCNTs), multi-wall carbon nanotubes (MWCNTs) and the mesoporous carbons (MPCs), and compared their morphology effects on both Ni–Ag deposition quality and electrocatalytic performances toward Glu oxidation. After being deposited with Ni–Ag NPs, a homogenous surface with very small Ni–Ag NPs was obtained for Ni–Ag/SWCNTs/GCE, while heterogeneous, coarse surfaces with obvious embedment with large Ni–Ag particles were observed for both Ni–Ag/MWCNTs/GCE and Ni–Ag/MPC/GCE. All three modified electrodes were well characterized in terms of surface morphology, electron transfer rate, hydrophilicity, interference resistance, stability, electrocatalytic behaviors as well as practicability in real samples, based on which Ni–Ag/SWCNTs/GCE was always proved to be more advantageous over other two composite electrodes. Such advantage of Ni–Ag/SWCNTs/GCE was attributed to its desirable surface morphology good for Ni–Ag deposition and exposure of as many active sites as possible to Glu oxidation, leading to the extraordinary electrocatalytic performance.

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Hayashi, Toshiyuki, Akihito Matsumuro, Mutsuo Muramatsu, Masao Kohzaki, and Katsumi Yamaguchi. "Wear resistance of carbon nitride thin films formed by ion beam assisted deposition." Thin Solid Films 376, no. 1-2 (November 2000): 152–58. http://dx.doi.org/10.1016/s0040-6090(00)01201-3.

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Journal articles on the topic 'Carbon deposition resistance'

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