Dehydriding reaction kinetic mechanism of MgH2-Nb2O5 by Chou model
来源期刊：中国有色金属学报(英文版)2008年增刊第1期
论文作者：刘杨 李谦 周国治
文章页码：235 - 241
Key words：MgH2 composite; Chou model; hydrogen desorbing mechanism
Abstract: Chou model was used to investigate the dehydriding reaction kinetic mechanism of MgH2-Nb2O5 hydrogen storage materials at 573 K. A new conception, “characteristic absorption/desorption time (tc)” was introduced to characterize the reaction rate. The fitting results show that for the hydrogen desorbing mechanism, the surface penetration is the rate-controlling step. The mechanism remains the same even when the original particle size of Nb2O5 is before ball milling (BM) or when the BM time changes. And tc indicates that the desorption rate of MgH2-Nb2O5 will be faster than that of MgH2-Nb2O5 by BM. The dehydriding reaction rate of MgH2-Nb2O5 (micro particle) BMed for 50 h is 4.76 times faster than that of the MgH2-Nb2O5 (micro particle) BMed for 0.25 h, while the dehydriding reaction rate of MgH2-Nb2O5 (nano particle) BMed for 50 h is only 1.18 times as that of the MgH2-Nb2O5 (nano particle) BMed for 0.25 h. The dehydriding reaction rate of the BMed MgH2-Nb2O5 (nano particle) is 1-9 times faster than that of the BMed MgH2-Nb2O5 (micro particle).
基金信息：the Shanghai Municipal Education Commission, China
the Science and Technology Commission of Shanghai Municipality, China
the Shanghai Rising-Star Program (A type), China
the Foundation for the Author of National Excellent Doctoral Dissertation of China
