Fig. 1: Motivation and design of electrocatalyst.

a Tuning strategy of the electronic structure of the MoS2 surface. b Design ideas of hydrogen evolution catalyst. c–f the energetics of hydroxyl species on 2Hphase-MoS2 (002), 1Tphase-MoS2 (002), NiS2 (210), and Ni2P (111) HER electrocatalyst surfaces. g Schematics of the 1T0.72-MoS2@NiS2 and 1T0.81-MoS2@Ni2P synthesis steps.