Doping and interface engineering in a sandwich Ti3C2Tx/MoS2−xPx heterostructure for efficient hydrogen evolution

Abstract

The development of low-cost, stable, and robust electrocatalysts for the hydrogen evolution reaction (HER) is significantly indispensable and is of urgent need for electrocatalytic water splitting and clean energy. Herein, a hydrothermal and phosphorization approach is reported for the construction of a sandwich Ti₃C₂T_x/MoS_2−xP_x heterostructure, in which ultrathin MoS₂ nanosheets doped with P are vertically grown on a 2D layered Ti₃C₂T_x MXene. The as-prepared Ti₃C₂T_x/MoS_2−xP_x heterostructure delivers outstanding activity for the HER, affording a low overpotential of 157 mV at 10 mA cm⁻², as well as superior long-term durability with a negligible attenuation after 2000 CV cycles and constant activity after the chronoamperometric test. An excellent HER performance is induced by ultrathin MoS₂ nanosheets, which bring abundant active sites to accelerate mass transport. Furthermore, the sandwich heterostructure shows an abundant interface and a 3D porous network, which can facilitate electron transfer capability and promote the contact of electrolytes. In addition, P doping provides good conductivity and has appropriate adsorption and desorption energy for the H intermediate. This work enriches the catalyst family and presents an alternative and efficient route to accelerate the hydrogen activity of non-noble metal catalysts.