增强反溢出和高效电化学脱的Rh单原子协调的调节
Qian Zheng1, Hengyue Xu2, Yancai Yao1
1State Key Laboratory of Green Papermaking and Resource Recycling, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Journal of the American Chemical Society
|November 12, 2025
概括
优化Rh单原子协调增强反向溢出,以实现高效的电化学化. 一个四氧协调的Rh电极 (Rh1O4) 在水电解中表现出卓越的性能,这对于可持续的催化是至关重要的.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 反向溢出 (RHS) 是电化学化的关键,它依赖于从催化剂表面转移原子.
- RHS的效率对单原子催化场的协调环境和电子结构非常敏感.
研究的目的:
- 在水电解过程中研究Rh单原子协调对氧化表面的影响.
- 将单个Rh原子的协调数与它们的电子结构和RHS效率相关联.
- 建立用于化反应的先进单原子电催化剂的设计框架.
主要方法:
- 使用Rh单原子功能化的泡电极进行电化学水电解.
- 单原子Rh协调环境 (Rh1O4,Rh1O5,Rh1O3) 和它们的电子结构的表征.
- 测量吸附的吉布斯自由能量 (ΔGH*) 和RHS能量障碍.
主要成果:
- 与Rh1O5和Rh1O3相比,四氧协调的Rh单原子电极 (Rh1O4) 显示出更高的RHS能力.
- Rh1O4实现了0.08 eV的优化ΔGH*和0.55 eV的降低RHS能量屏障.
- Rh1O4 的降解速率常数为 4. 65 h−1,显著超过 Rh1O5 (1. 18 h−1) 和 Rh1O3 (0. 16 h−1).
结论:
- 单原子协调工程对于调整RHS中的原子转移动态至关重要.
- Rh-O 协调数直接影响 Rh d 带中心,优化 H* 吸附和 RHS 效率.
- Rh1O4配置为开发可持续化的高性能单原子电催化剂提供了一个战略模型.
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