环境驱动的变量在绝对带边位置和减少的Ceria的工作功能
Xingfan Zhang1, Christopher Blackman2, Robert G Palgrave2
1Kathleen Lonsdale Materials Chemistry, Department of Chemistry, University College London, London WC1H 0AJ, U.K.
Journal of the American Chemical Society
|June 5, 2024
概括
环境条件的动态变化
科学领域:
- 材料科学
- 表面科学
- 计算化学
背景情况:
- 绝对带边位置和工作功能 (Φ) 对电子和光催化中的金属氧化物性能至关重要.
- 这些特性的实验测量显示出差异,基础机制不太清楚.
- (CeO2) 是一种具有高氧储存能力的关键材料,因此其电子性能至关重要.
研究的目的:
- 调查的电离潜力 (IP) 和工作功能的环境变化.
- 阐明氧气固体测量,表面物种和杂质对的电子性质的影响.
- 使用理论和实验方法合理化能量水平的变化.
主要方法:
- 结合了理论和实验技术.
- 混合量子力学/分子力学 (QM/MM) 嵌入式集群计算.
- 基于原子间电位的静电分析的周期密度函数理论 (DFT).
主要成果:
- 缺氧降低了的IP和Φ,对缺陷分布很敏感.
- 富含氧气的环境由于表面过氧化物形成而提高IP和Φ.
- 表面吸附物和杂质在现实条件下进一步增加了变性.
结论:
- 在现场的静电电位决定了金属氧化物的绝对能量水平.
- 在催化条件下,Ceria的波段边缘会动态演变.
- 了解这些环境影响对于优化基于ceria的设备至关重要.
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