Ag掺杂γ-MnO2酸性电催化析氧反应研究

高性能酸性电解水催化剂的开发是质子交换膜电解水技术的重要研究方向。在本工作中，通过将Ag掺杂到γ?MnO2（MO）中，获得了高性能Ag?MnO2（AMO）酸性析氧电催化剂。Ag的掺杂优化了MO的电子结构，提高了MO的析氧反应活性。最优催化剂获得10 mA/cm2电流密度的过电位为398 mV，比MO降低了28 mV。此外，Ag的掺杂提高了MO的反应稳定性。最优催化剂在100 mA/cm2的大电流密度下可稳定运行500小时以上，在高达500 mA/cm2的电流密度下也可稳定运行50小时以上，是目前在大电流密度工作条件下最稳定的非贵金属酸性析氧电催化剂之一。

Silver-Doped γ-MnO2 for Oxygen Evolution Reaction in Acidic Media

Water electrolysis with a proton exchange membrane (PEM) is an important technology for hydrogen production. The development of non-precious metal-based electrocatalysts that catalyze the oxygen evolution reaction efficiently and stably in acidic media is of great importance, but remains a major challenge. In this work, Ag is doped into γ?MnO2 (MO) to develop an Ag?MnO2 (AMO) electrocatalyst that enables a highly efficient acidic oxygen evolution reaction. We find that Ag doping optimizes the electronic structure of MO and improves its charge transfer ability. Therefore, AMO electrodes show much better oxygen evolution activity than MO electrodes. The optimized 7.5AMO electrode delivers current densities of 10 mA/cm2 at overpotentials of 398 mV in a 1.0 mol/L sulfuric acid solution, which is 28 mV less than the MO electrode. In addition, Ag doping significantly improves the stability of the MO for the acidic oxygen evolution reaction. At a high current density of 100 mA/cm2, the 7.5AMO electrode maintains a stable potential for more than 500 hours. Even more impressively, it remains stable for more than 50 hours at a current density of 500 mA/cm2. As far as we know, this is one of the most stable non-precious metal-based electrocatalysts for the acidic oxygen evolution reaction at high current densities.