Cobalt-based oxygen-evolving catalyst (Co-OEC) exhibits high catalytic activity for water oxidation in the neutral pH regime. However, as the externally applied potential toward oxidation is lowered, the catalyst is slowly dissolved and eventually decomposed from the electrode because of their poor interfacial compatibility. Here, we introduce an interstitial polydopamine (PDA) layer to strengthen the Co-OEC/electrode interface for sustainable catalytic activity. The PDA layer efficiently stabilizes the catalyst/electrode interface as a redox-active adhesive interlayer. Under high applied potential conditions, the oxygen evolving catalytic activity is reduced by 95 % in the absence of the PDA layer. On the other hand, the Co-OEC/PDA/ITO electrode keeps the catalytic activity above 70 % under the same condition because the redox mediation of PDA suppresses the dissolution of Co²⁺ ions. The PDA layer also promotes water oxidation catalysis presumably through proton-coupled electron transfer. It is expected that the redox-active PDA can be applied to various catalysts as a means to improve their microenvironments for enhanced catalytic activity and sustainability.

钴基析氧催化剂（Co-OEC）在中性pH值下对水氧化具有高催化活性。但是，随着外部施加的氧化电位降低，催化剂缓慢溶解并由于其不良的界面相容性而最终从电极上分解。在这里，我们引入了间隙聚多巴胺（PDA）层，以增强Co-OEC /电极界面的可持续催化活性。PDA层可以有效地稳定催化剂/电极界面，作为氧化还原活性粘合剂中间层。在高施加电势条件下，在没有PDA层的情况下，放出氧气的催化活性降低了95％。另一方面，²⁺离子。PDA层也可能通过质子耦合电子转移促进水氧化催化。预期氧化还原活性的PDA可以应用于各种催化剂，作为改善其微环境以增强催化活性和可持续性的手段。