Atomic doping resets the local electronic structure of a 2D V2C MXene-based heterointerface for efficient urea-assisted alkaline water splitting

The development of the efficient bifunctional hydrolysis electrocatalyst is of great significance. In this work, N, Ce co-doped CoO nanoparticles (NPs) in-situ growing few-layer V₂C-MXene interfacial structure (N, Ce-CoO NPs/MXene) has been developed as self-supporting electrodes for hydrogen production by interfacial engineering strategy. The integration of nanoparticles into the composite effectively mitigates the tendency of few-layer MXene sheets to undergo self-stacking, while simultaneously introducing a significant number of heterogeneous interfaces. The simultaneous doping of two distinct atoms modulates the electronic configuration of the active sites at heterogeneous interfaces, thereby enhancing the electron transfer processes occurring between the interfaces. The N, Ce-CoO NPs/MXene electrocatalysts exhibit excellent performance in both urea oxidation reaction (UOR) and hydrogen evolution reaction (HER), reaching 1.33 V and 86 mV at 10 mA cm^-2. The N, Ce-CoO NPs/MXene as a bifunctional catalyst for urea-assisted electrolysis can reach 10 mA cm^-2 at only 1.38 V with almost no performance degradation for 100 h. In-situ Raman spectroscopy reveals the main active sites of Co as a catalyst. Density functional theory (DFT) demonstrated that the N, Ce-CoO NPs/MXene interfacial catalysts facilitate electron transfer, thereby promoting the dissociation of urea molecules through the reorganization of electrons at the interface.