Amorphous MoS₂ confined in nitrogen-doped porous carbon for improved electrocatalytic stability toward hydrogen evolution reaction

Developing non-precious metal catalysts with high activity and stability for electrochemical hydrogen evolution reaction (HER) is of great significance in both science and technology. In this work, N-doped CMK-3, which was prepared with a casting method using SBA-15 as the hard template and ammonia as the nitrogen source, has been utilized to hold MoS₂ and restrict its growth to form MoS₂@N-CMK-3 composite. As a result, MoS₂ was found to have poorly crystallized and the limited space of porous N-CMK-3 made its size much small. Then there are more active sites in MoS₂. Accordingly, MoS₂@N-CMK-3 has exhibited good electrocatalytic performance toward HER in acids with a quite small Tafel slope of 32 mV·dec^-1. And more importantly, compared to MoS₂@CMK-3, its stability has been greatly improved, which can be attributed to the interaction between MoS₂ and nitrogen atoms avoiding aggregation and mass loss. This work provides an idea that doping a porous carbon support with nitrogen is an effective way to enhance the stability of the catalyst.