Scalable synthesis of Mo2C/CNT networks as highly efficient and stable electrocatalyst for hydrogen evolution reaction

Abstract

The efficient generation of clean hydrogen energy through the water splitting has attracted much more attention. However, lacking of low-cost and highly efficient electrocatalysts is still a major obstacle for hydrogen generation via hydrogen evolution reaction (HER). Herein, for the first time, we present a facile, low-cost and scalable synthesis of highly efficient and stable Mo2C/CNT hybrid via spray drying followed by carbonization process (Mo2C/CNT-SC). The optimized Mo2C/CNT-SC hybrid delivers superior HER performance with a low Tafel slop of 53.6 mV dec−1, and an extremely low onset overpotential of ∼20 mV (vs RHE) @ 1 mA cm−2, which is much lower than those of most reported electrocatalysts and comparable to that of Pt-based electrocatalysts. The Mo2C/CNT-SC hybrid also shows excellent stability even after 1000 cycles. The superior HER performance of Mo2C/CNT-SC can be attributed to its unique conductive and porous structure constructed by ultrasmall Mo2C nanoparticles homogenously embedded in CNT networks, which can not only provide sufficient HER active sites, but also guarantee full contact between the Mo2C nanoparticles and CNT networks. The principles demonstrated in our work can be extended to scalable synthesis of other non-noble metal electrocatalysts with excellent HER performance.