Rational design and controllable synthesis of efficient electrocatalysts for water oxidation is of significant importance for the development of promising energy conversion systems, in particular integrated photoelectrochemical water splitting devices. Cobalt oxide (Co₃O₄) nanostructures with mixed valences (II,III) have been regarded as promising electrocatalysts for the oxygen evolution reaction (OER). They are able to promote catalytic support of OER but with only modest activity. Here, we demonstrate that the OER performance of cubic Co₃O₄ electrocatalyst is obviously improved when they are anchored on delaminated two-dimensional (2D) Ti₃C₂ MXene nanosheets. Upon activation the overpotential of the hybrid catalyst delivers 300 mV at a current density of 10 mA cm⁻² in basic solutions, which is remarkably lower than those of Ti₃C₂ MXene and Co₃O₄ nanocubes. The strong interfacial electrostatic interactions between two components contribute to the exceptional catalytic performance and stability. The enhanced OER activity and facile synthesis make these Co₃O₄ nanocubes-decorated ultrathin 2D Ti₃C₂ MXene nanosheets useful for constructing efficient and stable electrodes for high-performance electrochemical water splitting.

合理设计和可控制地合成用于水氧化的高效电催化剂，对于开发有前途的能量转换系统（特别是集成的光电化学水分解装置）非常重要。具有混合化合价（II，III）的氧化钴（Co ₃ O ₄）纳米结构被认为是用于氧释放反应（OER）的有前途的电催化剂。它们能够促进OER的催化负载，但活性适中。在这里，我们证明，当立方钴₃ O ₄电催化剂固定在分层二维（2D）Ti ₃ C ₂上时，其OER性能得到明显改善。MXene纳米片。活化后，杂化催化剂的过电势在碱性溶液中以10 mA cm ^-2的电流密度提供300 mV的电势，该电势显着低于Ti ₃ C ₂ MXene和Co ₃ O ₄纳米立方体的电势。两个组分之间的强界面静电相互作用有助于实现出色的催化性能和稳定性。增强的OER活性和易于合成的特性使这些用Co ₃ O ₄纳米立方体装饰的超薄2D Ti ₃ C ₂ MXene纳米片可用于构建高效，稳定的电极，用于高性能电化学水分解。