Hybrid catalyst of MoS2-CoMo2S4 on graphene for robust electrochemical hydrogen evolution.

After years of development, boosting the electrochemical hydrogen evolution performance of MoS 2 catalyst through the traditional methods, such as defect engineering and conductivity improvement, has reached their limit. In this work, we propose a novel functional catalyst that is fabricated by hybrid two-dimensional nanostructures composed of MoS 2 nanosheets and CoMo 2 S 4 nanoplates in situ grown on graphene substrate for electrochemical hydrogen evolution reaction. The MoS 2 -CoMo 2 S 4 /graphene hybrid catalyst shows robust hydrogen evolution performance with low onset potential of 110 mV, high cathode current density of 85 mA cm −2 at η = 300 mV, and small Tafel slope of 42 mV dec −1 , as well as good durability. The excellent hydrogen evolution performance of the hybrid catalyst is likely attributed to the nonequilibrium composition, 2D structural advantages, conductive graphene substrate, and the electrocatalytic synergistic effect between MoS 2 and CoMo 2 S 4 . [ABSTRACT FROM AUTHOR]