Microstructural evolution of NbF5-doped MgH2 exhibiting fast hydrogen sorption kinetics

被引：48

作者：

Kim, Ji Woo ^{[2
,3
]}

Ahn, Jae-Pyoung ^{[1
]}

Jin, Seon-Ah ^{[3
]}

Lee, Sang Hoon ^{[2
]}

Chung, Hee-Suk ^{[2
]}

Shim, Jae-Hyeok ^{[3
]}

Cho, Young Whan ^{[3
]}

Oh, Kyu Hwan ^{[2
]}

机构：

[1] Korea Inst Sci & Technol, Adv Anal Ctr, Seoul 136791, South Korea

[2] Seoul Natl Univ, Dept Mat Sci & Engn, Seoul 151742, South Korea

[3] Korea Inst Sci & Technol, Mat Sci & Technol Res Div, Seoul 136791, South Korea

来源：

JOURNAL OF POWER SOURCES | 2008年 / 178卷 / 01期

关键词：

hydrogen storage; hydrides; transmission electron microscopy; focused ion beam; catalysts;

D O I：

10.1016/j.jpowsour.2007.12.005

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The microstructure of MgH(2) with 1 mol% NbF(5), Prepared by high-energy ball milling (HEBM), was studied using high resolution transmission electron microscopy (HR-TEM) with an X-ray energy dispersive spectrometer (EDS) before and after hydrogen sorption cycles. The TEM samples were prepared without any air exposure by a novel, focused ion beam (FIB) system specially designed for highly air sensitive materials. During HEBM, the doping agent, NbF5, was distributed as an extremely thin, film-like, amorphous phase along the grain boundaries of the nanocrystalline MgH2. After 10 sorption cycles, amorphous Nb-F phase was transformed into crystalline Nb hydrides. It is believed that the Nb hydride played a decisive role in improving the sorption kinetics of MgH(2). (C) 2007 Elsevier B.V. All rights reserved.

引用

页码：373 / 378

页数：6

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