三维巢状CNT@TiO_(2)的制备及其对NaAlH_(4)储氢性能的影响  

Preparation of Three-Dimensional Nest-Like CNT@TiO_(2)and Its Influence on Hydrogen Storage Performance of NaAlH_(4)

作　　者：陈晶晶 陈伟 夏广林 余学斌[1] CHEN Jingjing;CHEN Wei;XIA Guanglin;YU Xuebin(Department of Materials Science,Fudan University,Shanghai 200433,China)

机构地区：[1]复旦大学材料科学系,上海200433

出　　处：《西安工业大学学报》2025年第2期184-193,共10页Journal of Xi’an Technological University

基　　金：国家自然科学基金青年基金项目(52301264)。

摘　　要：NaAlH_(4)因其相对较低的脱氢温度和较高的储氢容量而被视为一种有良好使用前景的储氢材料。本文通过溶剂热和煅烧两步反应制备了三维巢状结构的CNT@TiO_(2),并研究了其作为催化剂对NaAlH_(4)储氢性能的影响。研究结果表明,在CNT@TiO_(2)的催化下,NaAlH_(4)的两步脱氢反应峰值温度为111℃和141℃,比纯NaAlH_(4)分别降低了141℃和126℃,两步脱氢反应的表观活化能分别降低到69.0 kJ·mol^(-1)和64.4 kJ·mol^(-1)。更重要的是,经10次吸放氢循环后,材料仍可保持4.5 wt.%的可逆储氢容量,容量保持率达到91%。这种良好的可逆储氢性能归因于CNT对TiO_(2)的分散作用和吸放氢过程中原位形成的Ti基催化剂(Ti_(2)O_(3)和金属Ti)的稳定催化作用。本研究为金属配位氢化物纳米催化剂的设计提供了新的思路。NaAlH_(4)is considered one of the most promising hydrogen storage materials due to its relatively low hydrogen desorption temperature and high hydrogen storage capacity.In this study,three-dimensional nest-like CNT@TiO_(2)was prepared through two-step reactions of solvothermal and calcination,and its effect as a catalyst on the hydrogen storage performance of NaAlH_(4)was investigated.The results show that under the catalysis of CNT@TiO_(2),the peak temperatures of the two-step hydrogen desorption reactions of NaAlH_(4)are 111℃and 141℃,respectively,which are reduced by 141℃ and 126℃ compared to pure NaAlH4.The apparent activation energies of the two-step hydrogen desorption reactions are reduced to 69.0 kJ·mol^(-1)and 64.4 kJ·mol^(-1),respectively.More importantly,after 10 cycles of hydrogen adsorption and desorption process,the reversible hydrogen storage capacity of NaAlH_(4)doped with 10 wt.%CNT@TiO_(2)maintains at 4.5 wt.%,with a capacity retention of 91%.This excellent reversible hydrogen storage performance is attributed to the uniform dispersion of TiO_(2)on CNT and the stable catalytic effect of in-situ formed Ti-based catalysts(Ti_(2)O_(3)and metallic Ti)during the hydrogen adsorption and desorption processes.This paper provides new ideas for the design of nano-catalysts to improve the hydrogen storage performance of complex hydrides.

关 键 词：NaAlH_(4) 储氢性能 催化 可逆储氢 

分 类 号：TQ032.4[化学工程]