The oxygen evolution reaction (OER) balances the hydrogen evolution reaction when splitting water into green hydrogen and oxygen with renewable electricity. Oxygen evolution occurs at potentials at which the pre-catalysts undergo transformations into complex and disordered OER-active oxides. Traditional synthetic methods and material compositions have resulted in an enormous variety of OER pre-catalysts, yet the most active of them are forced into a few prevailing oxyhydroxide or amorphous oxide phases under operation. As a result, practically relevant catalyst activity and stability have remained unchanged for decades. Here we discuss the need to develop new theory in synergy with operando electrochemical and spectroscopic characterization to take advantage of the effects of an applied electrochemical potential gradient on the chemical composition and atomic surface structure, the hydroxide ion intercalation and other interfacial ionics. Additionally, we highlight new synthesis methods and material compositions that might translate control over the pre-catalyst into control over the active oxide phase, as well as new methods of modifying active oxides during operation.

当利用可再生电力将水分解为绿色氢气和氧气时，析氧反应 (OER) 可以平衡析氢反应。在预催化剂转变为复杂且无序的 OER 活性氧化物的电位下，会发生析氧。传统的合成方法和材料组成已经产生了各种各样的 OER 预催化剂，但其中最活跃的在操作中被迫进入一些常见的羟基氧化物或无定形氧化物相。因此，实际相关的催化剂活性和稳定性几十年来一直保持不变。在这里，我们讨论需要开发与操作电化学和光谱表征协同的新理论，以利用所应用的电化学势梯度对化学成分和原子表面结构、氢氧根离子嵌入和其他界面离子的影响。此外，我们还重点介绍了新的合成方法和材料成分，这些方法和材料成分可能将对预催化剂的控制转化为对活性氧化物相的控制，以及在操作过程中改性活性氧化物的新方法。