-铁氧化氧化氧化进化电催化剂:故意和偶然的铁合并的作用
Lena Trotochaud1, Samantha L Young, James K Ranney
1Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States.
Journal of the American Chemical Society
|May 1, 2014
概括
铁 (Fe) 通过增强电子性质,显著增强了基于的氧化演化反应 (OER) 电催化剂. 净化电解质和理解Fe Fe.
科学领域:
- 电化学和材料科学 材料科学
- 专注于用于能源转换的催化剂.
背景情况:
- 基于的电催化剂对于氧化演化反应 (OER) 是至关重要的.
- 铁 (Fe) 含量增强了OER活动,但机制尚不清楚.
- 之前的研究可能会被电解质和材料中的Fe杂质所混.
研究的目的:
- 研究Fe在基于Ni的OER电催化剂中的作用.
- 为了阐明由Fe引起的电子和结构变化.
- 开发一种电解质净化方法,以去除Fe杂质.
主要方法:
- 电化学测量 (循环电压测量,活动与厚度对比).
- 在现场电导率和光电子光谱学.
- 用X射线衍射进行结构分析.
- 使用Ni(OH) 开发一种KOH电解质净化方法2.
主要成果:
- 没有Fe的Ni(OH) 2/NiOOH表现出明显的氧化还原特性和低OER活性.
- 混乱的γ-NiOOH比晶体β-NiOOH更活跃;β-NiOOH的活性增加是由于Fe杂质.
- 添加Fe可使膜导电率提高30倍以上,但仅此并不能解释活动增强.
- Fe可能对Ni产生部分电荷转移激活效应.
结论:
- 严格的Fe杂质去除对于准确的OER催化剂研究至关重要.
- 在Ni-Fe OER催化剂中Fe的主要作用是部分电荷转移激活.
- 这些发现为设计高活性Ni{1-x) Fe{-x) OOOH OER电催化剂提供了关键的见解.
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