苏州大学路建美小组取得一项新突破。她们的研究通过在范德华层状氧化铱中调制掺杂来优化酸性析氧反应。相关论文于2025年1月6日发表在《德国应用化学》杂志上。

据介绍，阳极析氧反应（OER）表现出一个缓慢的电子转运过程，需要具有特殊催化活性的催化剂来提高其动力学速率。范德华层状氧化物是催化剂设计的理想材料，但其在酸性OER中的稳定性仍是一大障碍。掺杂是同时提高活性和稳定性的重要途径。然而，在范德华层状氧化物中掺杂是一个很大的挑战，因为它容易导致晶格畸变甚至晶体结构破坏。

在这项工作中，课题组成功地通过碱辅助热方法，将耐酸铌（Nb）掺杂到范德华层状边缘共享1T相氧化铱（1T-IrO₂）中。掺入5% Nb （Nb_0.05Ir_0.95O₂）的1T-IrO₂在0.5 M H₂SO₄中仅需191 mV的过电位，即可达到10 mA cm^-2的电流密度，比1T-IrO₂低56 mV。当应用于质子交换膜水电解槽时，Nb_0.05Ir_0.95O₂在1.7 V的电池电压下达到1.2 A cm^-2的电流密度，持续50天。

密度泛函理论计算表明，Nb的掺入使电位决定步骤由1T-IrO₂中的*OOH去质子化过程，转变为Nb_0.05Ir_0.95O₂中的*O-OH偶联过程。

附：英文原文

Title: Optimizing Acidic Oxygen Evolution Reaction via Modulation Doping in Van der Waals Layered Iridium Oxide

Author: Jia Ke, Wenxiang Zhu, Yujin Ji, Jinxin Chen, Chenchen Li, Yue Wang, Qun Wang, Wei-Hsiang Huang, Zhiwei Hu, Youyong Li, Qi Shao, Jianmei Lu

Issue&Volume: 2025-01-06

Abstract: Anodic oxygen evolution reaction (OER) exhibits a sluggish four-electron transfer process, necessitating catalysts with exceptional catalytic activity to enhance its kinetic rate. Van der Waals layered oxides are ideal materials for catalyst design, yet its stability for acidic OER remains large obstacle. Doping provides a crucial way to improve the activity and stability simultaneously. However, doping in Van der Waals layered oxides remains a great challenge since it easily leads to lattice distortion or even the crystal structure damage. In this work, we successfully doping acid-resistant niobium (Nb) into Van der Waals layered edge-shared 1T phase iridium oxide (1T-IrO2) via alkali-assisted thermal method. 1T-IrO2 with a 5% Nb doping (Nb0.05Ir0.95O2) only required an overpotential of 191 mV to achieve a current density of 10 mA cm-2 in 0.5 M H2SO4, 56 mV lower than that of 1T-IrO2. When applied in a proton exchange membrane water electrolyzer, Nb0.05Ir0.95O2 achieved a current density of 1.2 A cm-2 at a cell voltage of 1.7 V for 50 days. Density functional theory calculation reveals that doping Nb changes the potential-determining step from the *OOH deprotonation process in 1T-IrO2 to the *O-OH coupling process in Nb0.05Ir0.95O2.

DOI: 10.1002/anie.202422740

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202422740