在共基层层氧化中水氧化活动的晶体和几何依赖性
Roger Sanchis-Gual1, Diego Hunt2, Camilo Jaramillo-Hernández1
1Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Valencia, Spain.
ACS catalysis
|August 10, 2023
概括
层氧化物对氧演化反应 (OER) 是有前途的. 具有独特四面体位的α-LH阶段,由于有利的电子性质和重建为活性氧化氧化物,显示出优越的OER性能.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 基于的分层氧化物 (LHs) 是氧演化反应 (OER) 的优秀电活性材料.
- 了解 Co-LH 的结构-活动关系对于 OER 仍然是一个挑战.
- 关键的晶体结构包括α-LH,β-LH和分层双氧化物 (LDH).
研究的目的:
- 调查晶体结构和协调几何学对二价联基LHsOER性能的影响.
- 阐明α-LH中四面体位点在增强OER催化中的作用.
- 为设计高效和稳定的开放式电源催化剂提供见解.
主要方法:
- 试验合成和α-LH,β-LH和LDH的表征.
- 对氧化演化反应 (OER) 性能进行电化学测试.
- 在密度函数理论 (DFT) 中的计算.
- 现场X射线衍射 (XRD) 和吸收光谱学.
主要成果:
- 与β-LH和LDH相比,α-LH显示出更高的OER催化活性.
- 对于α-LH,DFT的计算揭示了较低的超电位和有利的电子特性 (Egap).
- 实验结果表明,α-LH的有利重建进入了类似于Co (III) 氧化的阶段.
- 现场分析证实了α-LH稳定转化为高度反应的氧化氧化物结构.
结论:
- 晶体结构,特别是α-LH中四面体位点的存在,显著影响了OER性能.
- 四面体位点增强电子特性,并促进活性氧化氧化物种的形成.
- 这项研究为合理设计用于OER的先进的Co-LH电催化剂提供了基础.
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