天津大学梁红艳团队提出了Jahn−Teller活性掺杂剂通过深度氧化Co₄N激活晶格氧以改善电催化析氧。相关研究成果于2024年5月27日发表于国际顶尖学术期刊《德国应用化学》。

触发晶格氧氧化机制对于提高析氧反应（OER）性能至关重要，因为它可以通过直接形成氧-氧键，来绕过与传统吸附质析氧机制相关的标度关系限制。高价过渡金属位点有利于活化晶格氧，但预催化剂的深度氧化受到高热力学势垒的影响。

该文中，利用JahnTeller（JT）畸变引起的结构不稳定性，研究人员将高自旋Mn³⁺（t2g3eg1）掺杂剂掺入Co₄N中。如通过各种原位光谱研究所观察到的，Mn掺杂剂能够实现从Co₄N到CoOOH，最后到CoO₂的表面结构转变。此外，Mn掺杂的Co₄N上的重建表面触发了晶格氧活化，如pH依赖性OER、四甲基铵阳离子吸附和¹⁸O标记催化剂的在线电化学质谱测量所证明的那样。

总的来说，该项工作不仅提供了引入JT效应来调节结构转变的方法，而且还提供了对催化剂电子构型对确定反应路线的影响的理解，这可能会启发设计更有效的活性晶格氧催化剂。

附：英文原文

Title: Lattice Oxygen Activation through Deep Oxidation of Co4N by Jahn−Teller-active Dopants for Improved Electrocatalytic Oxygen Evolution

Author: Jingrui Han, Haibin Wang, Yuting Wang, Hao Zhang, Jun Li, Yujian Xia, Jieshu Zhou, Ziyun Wang, Mingchuan Luo, Yuhang Wang, Ning Wang, Emiliano Cort, Zumin Wang, Alberto Vomiero, Zhen-Feng Huang, Hangxing Ren, Xianming Yuan, Songhua Chen, Donghui Feng, Xuhui Sun, Yongchang Liu, Hongyan Liang

Issue&Volume: 2024-05-27

Abstract: Triggering the lattice oxygen oxidation mechanism is crucial for improving oxygen evolution reaction (OER) performance, because it could bypass the scaling relation limitation associated with the conventional adsorbate evolution mechanism through the directly formation of oxygenoxygen bond. High-valence transition metal sites are favorable for activating the lattice oxygen, but the deep oxidation of pre-catalysts suffers from a high thermodynamic barrier. Here, taking advantage of the JahnTeller (JT) distortion induced structural instability, we incorporate high-spin Mn3+ (t2g3eg1) dopant into Co4N. Mn dopants enable a surface structural transformation from Co4N to CoOOH, and finally to CoO2, as observed by various in-situ spectroscopic investigations. Furthermore, the reconstructed surface on Mn doped Co4N triggers the lattice oxygen activation, as evidenced experimentally by pH-dependent OER, tetramethylammonium cation adsorption and on-line electrochemical mass spectrometry measurements of 18O-labelled catalysts. In general, this work not only offers the introducing JT effect approach to regulate the structural transition, but also provides an understanding about the influence of catalyst’s electronic configuration on determining the reaction route, which may inspire the design of more efficient catalysts with activated lattice oxygen.

DOI: 10.1002/anie.202405839

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202405839