A series of molybdenum modified Ni/MgO catalysts （Ni-Mo/MgO） with different loading ratios of Ni ： Mo were prepared by impregnation method. Ethanol decomposition to co-produce multi-walled carbon nanotubes and hydr...A series of molybdenum modified Ni/MgO catalysts （Ni-Mo/MgO） with different loading ratios of Ni ： Mo were prepared by impregnation method. Ethanol decomposition to co-produce multi-walled carbon nanotubes and hydrogen-rich gas at temperatures of 600-800 ℃ was inves- tigated over the synthesized Ni-Mo/MgO catalysts. The results showed that the catalytic activity depended strongly on the reaction temperature and loading ratio of Ni ： Mo. According to the gaseous and solid products obtained, the reaction pathways for ethanol decomposition were suggested.展开更多
The effects of additives containing iron or nickel during chemical vapor deposition （CVD） on the growth of carbon nanotubes （CNTs） by methane decomposition on Mo/MgO catalyst were investigated. Ferrocene and nicke...The effects of additives containing iron or nickel during chemical vapor deposition （CVD） on the growth of carbon nanotubes （CNTs） by methane decomposition on Mo/MgO catalyst were investigated. Ferrocene and nickel nitrate were introduced as deactivation inhibitors by in-situ evaporation during CVD. The precisely controlled in-situ introduction of these inhibitors increased the surface renewal of catalyst, and therefore prevented the catalyst from deactivation. Using this method, aligned multi-walled CNTs with parallel mesopores can be produced on a large scale.展开更多
Effect of Y2O3-MgO addition on heterogeneous precipitation-thermal reduction synthesis and the sintering of Fe-Mo/Si3N4 powders has been investigated. It was found that the whiskers-like β-Si3N4, good wettability pha...Effect of Y2O3-MgO addition on heterogeneous precipitation-thermal reduction synthesis and the sintering of Fe-Mo/Si3N4 powders has been investigated. It was found that the whiskers-like β-Si3N4, good wettability phases on Si3N4 surface, and high toughness Fe phase appeared in Fe-Mo/Si3N4 cermets with Y2O3-MgO additives. The results show that Y2O3-MgO additives can effectively optimize the microstructures of Fe-Mo/ Si3N4 cermets, and improve the material mechanical properties. Therefore, it indicated that Y2O3-MgO additives can be used for strengthening of eintered cermets, and the dual function of whiskers self-toughening and different metal-composition toughening can be achieved in Fe-Mo/Si3N4 cermets with Y2O3-MgO additives.展开更多
基金A Foundation for the Author of National Excellent Doctoral Dissertation of PR China (200548)Natural Scientific Foundation of China (20606020,20736007)+1 种基金China National program (2006CB0N0702)Key Project of Chinese Ministry of Education(106011)~~
基金supported by the International Cooperation Research Program of the National Natural Science Foundation of China(No.21061130551)the NWU Training Program of Innovation and Entrepreneurship for Undergraduates(No.201210697012)the National Natural Science Foundation of China(Nos.J1210057 and J1103311)
文摘A series of molybdenum modified Ni/MgO catalysts （Ni-Mo/MgO） with different loading ratios of Ni ： Mo were prepared by impregnation method. Ethanol decomposition to co-produce multi-walled carbon nanotubes and hydrogen-rich gas at temperatures of 600-800 ℃ was inves- tigated over the synthesized Ni-Mo/MgO catalysts. The results showed that the catalytic activity depended strongly on the reaction temperature and loading ratio of Ni ： Mo. According to the gaseous and solid products obtained, the reaction pathways for ethanol decomposition were suggested.
基金This work was supported by the Guangdong Provincial Natural Science Foundation(No.31420)the Guangzhou City Science andTechnology Project(No.2003Z3-D2071)the Guangdong Provincial Science and Technology Project (No.2006 A10903002).
文摘The effects of additives containing iron or nickel during chemical vapor deposition （CVD） on the growth of carbon nanotubes （CNTs） by methane decomposition on Mo/MgO catalyst were investigated. Ferrocene and nickel nitrate were introduced as deactivation inhibitors by in-situ evaporation during CVD. The precisely controlled in-situ introduction of these inhibitors increased the surface renewal of catalyst, and therefore prevented the catalyst from deactivation. Using this method, aligned multi-walled CNTs with parallel mesopores can be produced on a large scale.
基金supported by the National Natural Science Foundation of China (Nos. 51274093 and 50804016)the Key Discipline Project Foundation of Hunan Province, China (No. 0805)
文摘Effect of Y2O3-MgO addition on heterogeneous precipitation-thermal reduction synthesis and the sintering of Fe-Mo/Si3N4 powders has been investigated. It was found that the whiskers-like β-Si3N4, good wettability phases on Si3N4 surface, and high toughness Fe phase appeared in Fe-Mo/Si3N4 cermets with Y2O3-MgO additives. The results show that Y2O3-MgO additives can effectively optimize the microstructures of Fe-Mo/ Si3N4 cermets, and improve the material mechanical properties. Therefore, it indicated that Y2O3-MgO additives can be used for strengthening of eintered cermets, and the dual function of whiskers self-toughening and different metal-composition toughening can be achieved in Fe-Mo/Si3N4 cermets with Y2O3-MgO additives.
