单壁碳纳米管和金属催化剂对MgH₂吸氢/脱氢性能的影响。

Effects of SWNT and metallic catalyst on hydrogen absorption/desorption performance of MgH2.

作者信息

Wu Chengzhang, Wang Ping, Yao Xiangdong, Liu Chang, Chen Demin, Lu Gao Qing, Cheng Huiming

机构信息

Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China.

出版信息

J Phys Chem B. 2005 Dec 1;109(47):22217-21. doi: 10.1021/jp0545041.

DOI:10.1021/jp0545041

PMID:16853892

Abstract

The microstructure and absorption/desorption characteristics of composite MgH2 and 5 wt % as-prepared single-walled carbon nanotubes (MgH2-5ap) obtained by the mechanical grinding method were investigated. Experimental results show that the MgH2-5ap sample exhibits faster absorption kinetics and relatively lower desorption temperature than pure MgH2 or MgH2-purified single-walled carbon nanotube composite. Storage capacities of 6.0 and 4.2 wt % hydrogen for the MgH2-5ap composite were achieved in 60 min at 423 and 373 K, respectively. Furthermore, its desorption temperature was reduced by 70 K due to the introduction of as-prepared single-walled carbon nanotubes (SWNTs). In addition, the different effects of SWNTs and metallic catalysts contained in the as-prepared SWNTs were also investigated and a hydrogenation mechanism was proposed. It is suggested that metallic particles may be mainly responsible for the improvement of the hydrogen absorption kinetics, and SWNTs for the enhancement of hydrogen absorption capacity of MgH2.

摘要

研究了通过机械研磨法制备的复合MgH₂与5 wt%的原位单壁碳纳米管（MgH₂-5ap）的微观结构以及吸/脱附特性。实验结果表明，与纯MgH₂或MgH₂-纯化单壁碳纳米管复合材料相比，MgH₂-5ap样品表现出更快的吸氢动力学和相对较低的脱附温度。MgH₂-5ap复合材料在423 K和373 K下分别于60分钟内实现了6.0 wt%和4.2 wt%的储氢容量。此外，由于原位单壁碳纳米管（SWNTs）的引入，其脱附温度降低了70 K。另外，还研究了原位SWNTs中所含SWNTs和金属催化剂的不同作用，并提出了氢化机理。研究表明，金属颗粒可能主要负责吸氢动力学的改善，而SWNTs则负责提高MgH₂的吸氢容量。