Synthesis of Mo2C/MoC and Mo2C/MoC/MoP heterostructures supported on N-doped carbon as electrocatalyst for high-efficient hydrogen evolution reaction

Abstract

Electrochemical water splitting is considered a sustainable route for the hydrogen industry. In this work, Mo2C/MoC heterostructure supported on N-doped carbon (Mo2C/MoC@NC) was prepared via a carbonization strategy. For the product (Mo2C/MoC@NC-1-2) fabricated with a g-C3N4/ ammonium molybdate tetrahydrate molar ratio of 1:2 at 700 °C under 10%CH4/H2 atmosphere, a high stability and good HER activity with a η10 of 113 mV in 1M KOH were achieved. To further enhance the catalytic performance of the synthesized Mo2C/MoC@NC, the phosphating strategy was proposed for the preparation of Mo2C/MoC/MoP heterostructure supported on N-doped carbon (Mo2C/MoC/MoP@NC). When the precursor Mo2C/MoC@NC-1-2 was phosphated at 650 °C with a heating rate of 5 °C min−1 and kept for 0 min, the as-synthesized Mo2C/MoC/MoP@NC-650-0 exhibits good HER catalytic activity with a pretty low η10 of 78 mV, a j0 of 0.398 mA cm−2, and a Tafel slope of 52 mV dec−1 in 1M KOH. This good activity of HER can be ascribed to the N-doped carbon as substrate and the construction of transition metal-based heterostructures.