确定用于绿色气生产的矿氧化物的通用活动描述器和统一机制概念
Daqin Guan1,2, Hengyue Xu3, Qingwen Zhang4
1WA School of Mines: Minerals, Energy, and Chemical Engineering, Curtin University, Perth, Western Australia, 6845, Australia.
Advanced materials (Deerfield Beach, Fla.)
|July 15, 2023
概括
一个新的通用描述符,轨道电荷转移能量 (Δ),准确地预测了和氧进化反应 (HER/OER) 催化剂活性. 最佳 Δ ≈ 1 eV揭示了对水电解的电催化剂机制的洞察.
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:
- 水电解对于可持续的和氧生产至关重要.
- 现有的演化反应 (HER) 和氧演化反应 (OER) 的电催化剂缺乏通用活动描述符和统一的机制理解.
- 开发高效的催化剂是推动水电解技术发展的关键.
研究的目的:
- 在3d金属氧化物中建立HER和OER活性的通用描述符.
- 开发一个统一的概念,以了解 HER 和 OER 机制.
- 引导水电解的先进电催化剂的合理设计.
主要方法:
- 在三个电解质中的12个3d金属氧化物中,统计分析将材料特性与HER/OER活动相关联.
- 计算建模和实验验证.
- 作为描述符的轨道电荷转移能量 (Δ) 的研究.
主要成果:
- 轨道电荷转移能量 (Δ) 被确定为HER/OER活动的通用描述符.
- 一个最佳的 Δ ≈ 1 eV,在费米水平的特定电子密度,产生最高的催化活性,坚持萨巴蒂耶的原则.
- 具有最佳 Δ 的纯氧化物表现出高价值配置和活跃的晶格氧位点,促进质子吸附 (HER) 和晶格氧参与 (OER).
- 反应后的状态 (HER中的金属,OER中的氧化物) 还有助于催化活性.
结论:
- 轨道电荷转移能量 (Δ) 为预测和优化水电解的电催化剂性能提供了强大的工具.
- 统一的轨道电荷转移理论解释了这些氧化物上HER和OER的基本机制.
- 这项研究为设计高效和选择性电催化剂为可持续能源应用奠定了基础.
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