本文介绍利用X光吸收光谱技术分析能源材料,并以此分析技术,了解材料中目标吸收元素之价数、d轨域电子密度与局部环境变化,深究能源材料之材料物化特性,以藉此解释其电化学特性,甚至做进一步之性能提升.文中,分别以燃料电池电极之电化学纳米触媒与锂电池电极材料为例,说明X光吸收光谱技术之分析能力,并与材料之电化学特性建立关联.
The aim of this review is to introduce the characterization of energy materials by X-ray absorption spectroscopy (XAS) . This technique allows us to probe changes in the valance state and the local environment of the targeted element in the active material; thereby,leading to a better understanding of its electrochemical behavior,and hopefully showing the way to improved performance. Here,electrocatalysts for fuel cells and active electrode materials for Li-ion batteries are taken as the examples that illustrate the capability of XAS and allow observation and theory to be correlated with electrochemical phenomena.
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