氧空位通常被认为在析氧反应（OER）中起着至关重要的作用。然而，氧空位产生的活性位点的产生不可避免地受到其缩合和消除反应的限制。
为了克服这一限制，研究人员展示了一种新的光电重建策略，将原子分散的Cu掺入超薄（约2–3分子）无定形氢氧化物（a-CuM，M=Co、Ni、Fe或Zn）中，促进重建的氢氧化物去质子化以产生高价Cu。
原位XAFS结果和第一性原理计算表明，由于Jahn–Teller畸变，在OER过程中，Cu原子稳定在高价，导致对位型双氧空位作为动态稳定的催化位点。最佳a-CuCo催化剂在300 mV的过电位下表现出创纪录的3404.7A g–1的高质量活性，优于基准氢氧化物和氧化物催化剂。
所开发的光电重建策略开辟了一条通过高价铜单位点原位构建稳定氧空位的新途径，扩展了创建动态稳定活性位点的设计规则。
附：英文原文
Title: High-Valence Cu Induced by Photoelectric Reconstruction for Dynamically Stable Oxygen Evolution Sites
Author: Zhi Cai, Lidong Li, Peijia Ding, Dawei Pang, Mingyuan Xu, Ziyan Xu, Jianxin Kang, Tianqi Guo, Gilberto Teobaldi, Zhongchang Wang, Li-Min Liu, Lin Guo
Issue&Volume: June 29, 2024
Abstract: Oxygen vacancies are generally considered to play a crucial role in the oxygen evolution reaction (OER). However, the generation of active sites created by oxygen vacancies is inevitably restricted by their condensation and elimination reactions. To overcome this limitation, here, we demonstrate a novel photoelectric reconstruction strategy to incorporate atomically dispersed Cu into ultrathin (about 2–3 molecular) amorphous oxyhydroxide (a-CuM, M = Co, Ni, Fe, or Zn), facilitating deprotonation of the reconstructed oxyhydroxide to generate high-valence Cu. The in situ XAFS results and first-principles calculations reveal that Cu atoms are stabilized at high valence during the OER process due to Jahn–Teller distortion, resulting in para-type double oxygen vacancies as dynamically stable catalytic sites. The optimal a-CuCo catalyst exhibits a record-high mass activity of 3404.7 A g–1 at an overpotential of 300 mV, superior to the benchmarking hydroxide and oxide catalysts. The developed photoelectric reconstruction strategy opens up a new pathway to construct in situ stable oxygen vacancies by high-valence Cu single sites, which extends the design rules for creating dynamically stable active sites.
DOI: 10.1021/jacs.4c04975
