Promoting effect of MXenes on 1T/2H–MoSe2 for hydrogen evolution

Abstract

Cost-effective electrocatalysts are imperative to the large-scale hydrogen evolution reaction. Herein, 1T/2H–MoSe₂/Ti₃C₂ composites are integrated via a hydrothermal method by taking advantage of the tunable phases of MoSe₂ and high conductivity of Ti₃C₂. Consequently, the 1T/2H–MoSe₂/Ti₃C₂ composites exhibit an optimal overpotential of 150 mV at 10 mA cm⁻², a low Tafel slope of 90 mV dec⁻¹, and a steady catalytic activity for over 30 h in an alkaline environment. The improved HER performances can be ascribed to the introduction of the Ti₃C₂ support in a proper proportion, which not only makes the charge transfer process more convenient but also helps the dispersion of MoSe₂. Furthermore, the formation of MoSe₂/Ti₃C₂ heterogeneous interfaces and the synergistic effects stemming from the intimate interactions between the individual components ultimately boost the H₂O dissociation in the Volmer step. This study indicates that Ti₃C₂ is an ideal conductive support for improving HER catalytic activity, and paves a new way for other transition metal selenides and MXenes to build highly efficient HER electrocatalysts.