MoC nanodots toward efficient electrocatalytic hydrogen evolution: An interlayer-confined strategy with 2D-zeolite precursor

An efficient electrocatalyst of molybdenum carbide nanodots on carbon nanosheets (nano-MoC/C-Ns) is prepared via a novel interlayer-confined strategy with the aid of MCM-22(P), a kind of multilayered two-dimensional (2D) zeolite precursor. In this strategy, the confined space of the surfactant-swollen MCM-22(P) plays a critical role in creating a unique sandwich-like structure with Mo-based organic–inorganic nanohybrids which further in situ evolve into ultrafine ∼2 nm MoC nanodots on carbon nanosheets in the following carbonization process. After etching the zeolite layers, the nano-MoC/C-Ns is successfully obtained as an efficient noble-metal-free electrocatalyst for hydrogen evolution. The intimate contact between ultrafine MoC nanodots and C nanosheets, as well as their synergetic effects, endows this catalyst with large exposed active sites and accelerated electron transport. The optimal sample achieves excellent hydrogen evolution reaction performance in acidic, neutral and alkaline media with low η10 values of 126, 185 and 92 mV (vs. the values of 28, 36 and 37 mV for a Pt/C reference in acidic, neutral and alkaline media), respectively. This synthetic strategy provides some hints for designing high-performance carbides for energy conversion and storage.