Interface Engineering of an Ultrathin Hierarchical Phosphorus-Doped MoS2/Ni3S2 Heterostructure on Nickel Foam for Efficient Water Splitting

Rationally designed structures and elements are important for the construction of effective electrocatalysts for water splitting. Herein, we developed an ultrathin hierarchical P-doped MoS2/Ni3S2 heterostructure on nickel foam (NF) by a one-pot synthesis. Owing to its optimized electronic structure configuration and hierarchical structure with plenty of active sites, the optimized catalyst P1.0-doped MoS2/Ni3S2/NF showed promising activity for both hydrogen evolution reaction and oxygen evolution reaction in an alkaline medium requiring an overpotential of, respectively, 0.449 and 0.239 V at 100 mA cm–2. Furthermore, the P1.0–MoS2/Ni3S2/NF electrode was applied for overall water splitting using a two-electrode system. The electrolyzer achieved low cell voltages of 1.50 and 1.65 V at current densities of, respectively, 20 and 40 mA cm–2 with excellent stability over 60 h when compared with previously reported Ni3S2-based materials. The results obtained in this work highlight the prime combination of doping and interface engineering for the design of advanced materials in electrocatalysis.