Enhanced hydrogen absorption kinetics for hydrogen storage using Mg flakes as compared to conventional spherical powders
Enhanced hydrogen absorption kinetics for hydrogen storage using Mg flakes as compared to conventional spherical powders
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DOI：
10.1016/j.jpowsour.2008.05.033
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发表时间：
2008-09
影响因子：
9.2
通讯作者：
Ki‐Joon Jeon;Alexandros Theodore;Chang-Yu Wu
中科院分区：
文献类型：
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作者：
Ki‐Joon Jeon;Alexandros Theodore;Chang-Yu Wu
金属氢化物(如氢化镁)用于储氢的实际挑战主要在于改善吸氢动力学和容量。改善镁的动力学的方法通常包括改变颗粒几何形状、减小微晶尺寸和在金属表面涂覆催化过渡金属，如镍。本研究旨在通过一种新的方法来提高镁的储氢动力学和储氢容量，该方法利用包覆镍纳米催化剂的高长径比粉末(大直径金属薄片)。利用高速轨道球(HSOBM)处理机制备了片状材料。采用干法机械包覆的纳米Ni催化剂包覆镁粉，比传统的球形颗粒具有更好的吸放氢性能和更好的储氢能力。几何形状是吸氢动力学的重要影响因素，其影响比微晶尺寸的影响更大。
Practical challenges of metal hydrides for hydrogen storage such as magnesium hydride, lie predominantly in improving hydrogen absorption kinetics and capacity. Approaches to improving kinetics of Mg commonly include changing particle geometry, reducing crystallite size and coating with catalytic transition metals such as Ni. This study is aimed at improving the hydrogen storage kinetics and capacity of Mg by a novel approach utilizing high aspect ratio powders (thin metal flakes with large diameters) coated with a Ni nano-catalyst. A high speed orbiting ball media (HSOBM) processor was utilized to fabricate the flake-shaped materials. Mg flakes effectively coated with Ni nano-catalyst using dry mechanical coating were found to possess more favorable hydrogen absorption/desorption characteristics and improved hydrogen storage capacity than traditional spherical particles. Geometric shape was shown to be a vital factor in hydrogen absorption kinetics and its effects proved to be dominant over those of crystallite size.