Interfacial Coupling and Defect-Induced Dual Effects Enabling Superhydrophilic Ni2P/V2O3-X Heteronanosheets to Accelerate Alkaline Hydrogen Evolution Reaction

Searching high-performance and low-cost electrocatalysts for the hydrogen evolution reaction (HER) is highly desirable but still remains a sustained challenge, especially in alkaline media. Herein, we report the readily preparation of self supported Ni2P/V2O3-x heteronanosheets on nickel foam (NF) as an active and robust catalyst for the alkaline HER via a hydrothermal method followed by a phosphorization treatment. Our experimental studies and density functional theory (DFT) calculations suggested that these two constituent phases (Ni2P and V2O3-x) optimized by the interfacial coupling and defect-induced dual effects cooperatively work together to improve the inherent activity of the catalyst. Impressively, the introduction of the abundant oxygen-defect in the V(2)O(3-x)specie resulted in the improvement of its electrical conductivity, which in tight contact with the metalloid Ni2P endowed the catalyst with high electron transfer capability. Meanwhile, the unique superhydrophilic nanostructure of the catalyst promises the maximized utilization of active sites. As a consequence of the contribution of these benefits, the as-prepared Ni2P/V2O3-x/NF heterostructure electrocatalyst exhibits high catalytic performance and excellent stability for the alkaline HER, outperforming most existent non-noble metal electrocatalysts. This work highlights the potential of the rational combination of defect-rich metal oxides and transition metal phosphides to construct highly efficient heterostructure electrocatalysts toward the alkaline HER.