Constructing 3D interweaved MXene/graphitic carbon nitride nanosheets/graphene nanoarchitectures for promoted electrocatalytic hydrogen evolution

Abstract

The technique of electrocatalytic hydrogen evolution reaction (HER) represents a development trend of clean energy generation and conversion, while the electrode catalysts are bound to be the core unit in the electrochemical HER system. Herein, we demonstrate a bottom-up approach to the construction of three-dimensional (3D) interconnected ternary nanoarchitecture originated from Ti3C2Tx MXene, graphitic carbon nitride nanosheets and graphene (MX/CN/RGO) through a convenient co-assembly process. By virtue of the 3D porous frameworks with ultrathin walls, large specific surface areas, optimized electronic structures, high electric conductivity, the resulting MX/CN/RGO nanoarchitecture expresses an exceptional HER performance with a low onset potential of only 38 mV, a small Tafel slop of 76 mV dec−1 as well as long lifespan, all of which are more competitive than those of the bare Ti3C2Tx, g-C3N4, graphene as well as binary MX/RGO and CN/RGO electrocatalysts. Theoretical simulations further verify that the ternary MX/CN/RGO nanoarchitecture with ameliorative band structure is able to facilitate the electron transport and meanwhile offer multistage catalytically active sites, thereby guaranteeing rapid HER kinetics during the electrocatalytic process.