中性析氧反应对于新能源转换与存储领域而言意义十分重大。然而，缓慢的质子耦合电子转移步骤限制了析氧反应的整体效率。因此，开发高活性的中性析氧催化剂具有十分重要的研究价值。本文通过一种简便的策略成功制备出离子液体（IL）修饰的CoSn(OH)₆纳米立方体（命名为CoSn(OH)₆-IL）。修饰的离子液体并未改变CoSn(OH)₆的结构特征，但可有效调控活性位点附近的质子活性。与未经修饰的CoSn(OH)₆纳米立方体相比较而言，CoSn(OH)₆-IL对中性析氧反应展示出更高的本征活性。例如，在1.8 V（相对于可逆氢电极）的电压下，CoSn(OH)₆-IL的析氧电流密度是CoSn(OH₎₆的4倍。根据pH依赖性实验、原位电化学阻抗图谱、化学探针实验和同位素效应等测试结果可以得出，CoSn(OH)₆-IL催化剂中的界面离子液体可以作为质子转移介体，促进中性析氧反应的质子转移速率并提高析氧中间体的表面覆盖度，有效降低活化能垒，最终能够加速析氧反应动力学。这项工作提供了一种简单且有效的策略促进质子耦合电子转移过程，并有利于指导析氧催化剂的合理设计。

The development of highly active catalyst in pH-neutral media for oxygen evolution reaction (OER) is critical in the field of renewable energy storage and conversion. Nevertheless, the slow kinetics of proton-coupled electron transfer (PCET) hinders the overall OER efficiency. Herein, we report an ionic liquid (IL) modified CoSn(OH)₆ nanocubes (denoted as CoSn(OH)₆-IL), which could be prepared through a facile strategy. The modified IL would not change the structural characteristics of CoSn(OH)₆, but could effectively regulate the local proton activity near the active sites. CoSn(OH)₆-IL exhibits higher intrinsic OER performances than the pristine CoSn(OH)₆ in neutral media. For example, the current density of CoSn(OH)₆-IL at 1.8 V versus reversible hydrogen electrode (RHE) is about 4 times higher than that of CoSn(OH)₆. According to the pH-dependent kinetic investigations, operando electrochemical impedance spectroscopy, chemical probe tests and deuterium kinetic isotope effects, the interfacial layer of IL can be utilized as a proton transfer mediator to promote the proton transfer, which enhances the surface coverage of OER intermediates and reduces the activation barrier. Consequently, the sluggish OER kinetics is efficiently accelerated. This study provides a facile and effective strategy to facilitate the PCET processes and is beneficial to guide the rational design of OER electrocatalysts.