3D MOF-derived Co-doped Cu3P/NC octahedra embedded in 2D MXene nanosheets for efficient energy conversion

Designing hierarchical nanostructures and modulating the electronic structure are effective strategies for boosting the electrochemical performance of catalysts. Herein, a novel Co-Cu3P/NC@MXene catalyst with a unique 3D@2D structure is successfully fabricated through an in situ growth strategy. Metal–organic framework (MOF)-derived Co-Cu3P/NC octahedra are embedded in the interlayer gap of MXene, thereby creating a microenvironment that accelerated electron and mass transport. The incorporation of Co modulated the electronic structure of Cu3P, enhancing the electrochemical activity of the Co-Cu3P/NC@MXene catalyst. Furthermore, the hierarchical structure, constructed by combining 3D Cu3P/NC and 2D MXene, provided abundant electron transfer paths for the 3D@2D hybrid catalyst. As a result, Co-Cu3P/NC@MXene exhibited remarkable performance as a cathode in an alkaline electrolyte, reaching a lower overpotential of 110 mV vs. RHE, as well as a smaller Tafel slope of 62 mV dec−1. Furthermore, the power conversion efficiency (PCE) of the photovoltaics assembled with the Co-Cu3P/NC@MXene counter electrode was 8.18%, surpassing that of traditional Pt electrode-based devices (7.13%). This work offers a possible method for the controllable construction of MOF@MXene-based catalysts with hierarchical structures and tailored electronic structures for energy conversion applications.