磷化钴@铁-锌双金属磷化物多级纳米复合物的制备及其电催化水分解性能

Abstract Hierarchical nanostructures have attracted widespread interest owing to their unique properties compared to their bulk counterparts. Thus, they are considered promising electrocatalytic materials. In this work, a novel hierarchical porous nanocomposite of cobalt phosphide nanocage@ferric-zinc mixed-metal phosphide nanotubes (denoted CoP@ZnFeP) was fabricated using a self-assembly approach. Because of their structural and compositional merits, the as-prepared phosphide hybrids have abundant catalytic active sites and high porosity for facile mass diffusion. In an alkaline electrolyte, the CoP@ZnFeP flower-like hybrids displayed enhanced catalytic activity for the hydrogen evolution reaction and the oxygen evolution reaction compared with a mechanical mixture of CoP and ZnFeP nanoparticles. The CoP@ZnFeP hierarchical nanocomposites also showed excellent activity for the overall water splitting reaction, yielding a water-splitting current of 10 mA/cm2 on the application of just 1.6 V, as well as excellent durability (24-h long-term operation) in a two-electrode system. Our design methodology may create opportunities to search for highly efficient and robust non-precious metal catalysts with applications in high-performance energy conversion and storage devices.