Phosphorus Doping Induced Mos2@Ni3s2 Heterostructure Reformation Drives Remarkably Improved Hydrogen Evolution in Alkaline Electrolyte

Abstract

Integrating the advantages of heteroatom doping and heterostructures is a feasible strategy to meliorate the morphology and microstructure of hydrogen evolution reaction (HER) catalyst. Here, we propose an approach for in situ growing P-doped MoS2@Ni3S2 heterostructure electrocatalyst with unique electronic properties and enriched accessible active sites on nickel foam (NF) substrate. The preparation method requires only one step hydrothermal treatment, which is simple, easy to control the generated active phases, and energy-saving. A combined experimental and theoretical calculations identified that P doping and the construction of MoS2@Ni3S2 heterostructure can meliorate the interfacial atomic arrangement, regulate morphology, reform the local electronic configuration, promote fast charge transfer, and optimize the H* adsorption/desorption energy. Meanwhile, the unique stripe-geometry structure nanostructure composed of extremely thin nanosheets of P-MoS2@Ni3S2/NF significantly facilitates exposure and efficient utilization of the active sites. As a result, P-MoS2@Ni3S2/NF exhibits impressive HER performance. It requires merely overpotential of 65 mV to reach 10 mA·cm-2 with Tafel slope of 41.6 mV‧dec-1 in alkaline electrolyte, showing a 2.55-fold decrease in overpotential and a 0.85-fold decrease in Tafel slope compared with original MoS2/NF, which is considerably lower than most of the reported transition metal sulfides.

Keywords: Hydrogen evolution reaction, MoS2, Electrocatalysts, Phosphor doping, Heterostructure