Multi-dimensional MoS2/S-doped-CoP heterostructure nanoarrays as an efficient electrocatalyst for hydrogen evolution reaction

Abstract

Developing efficient and economical electrocatalysts for hydrogen evolution reaction (HER) over a broad pH range has received considerable attention. In this work, we prepared multi-dimensional MoS2/S-CoP heterojunction catalysts by utilizing the carbon clothes supported ZIF-67 array as templates combining with Mo-ion exchange and high-temperature phosphorization-sulfidation strategy. The introduction of MoS2 into S-CoP results in electron redistribution and the formation of a distinctive space charge region at the two-phase contact interface, thereby effectively tuning surface properties, enhancing electron conductivity, and improving electrocatalytic activity. According to Density Functional Theory (DFT) calculations, the introduction of MoS2 is advantageous for the adsorption and desorption of H*, resulting in the value of ΔGH* very close to zero. Furthermore, the adsorbed water molecules are more readily activated, rendering the ΔGH2O-dis decrease, thus significantly promoting HER activity. These features contribute to robust HER electrocatalytic performance in a wide pH range and even in seawater, which is also beneficial for industrial applications. In particular, MoS2/S-CoP exhibits superior HER performance in alkaline seawater, requiring only 197 and 228 mV to reach the current densities of 100 and 200 mA cm-2, respectively. This study offers novel perspectives on high-performance heterostructures for HER electrocatalysts in alkaline seawater environments.