期刊
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
卷 46, 期 53, 页码 27096-27106出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.ijhydene.2021.05.180
关键词
Magnesium; Lanthanum; Sodium; Metal hydrides; Hydrogen absorption kinetics
资金
- Australian Research Council (ARC) [LP160100690]
- Australian Government Research Training Program (RTP) Scholarship
- ARC [FL170100101]
- Australian Government
- Australian Research Council [LP160100690] Funding Source: Australian Research Council
Adding Na to cast Mg-La alloys significantly improves hydrogen absorption kinetics during the first activation cycle. The role of Na in Mg-La alloys has been discussed based on microstructural observations, crystallography, and first principles calculations.
With superior properties of Mg such as high hydrogen storage capacity (7.6 wt% H/MgH2), low price, and low density, Mg has been widely studied as a promising candidate for solid-state hydrogen storage systems. However, a harsh activation procedure, slow hydrogenation/dehydrogenation process, and a high temperature for dehydrogenation prevent the use of Mg-based metal hydrides for practical applications. For these reasons, Mg-based alloys for hydrogen storage systems are generally alloyed with other elements to improve hydrogen sorption properties. In this article, we have added Na to cast Mg-La alloys and achieved a significant improvement in hydrogen absorption kinetics during the first activation cycle. The role of Na in Mg-La has been discussed based on the findings from microstructural observations, crystallography, and first principles calculations based on density functional theory. From our results in this study, we have found that the Na doped surface of Mg-La alloy systems have a lower adsorption energy for H-2 compared to Na-free surfaces which facilitates adsorption and dissociation of hydrogen molecules leading to improvement of absorption kinetic. The effect of Na on the microstructure of these alloys, such as eutectic refinement and a density of twins is not highly correlated with absorption kinetics. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据