Electrochemically exfoliated Ni-doped MoS_(2) nanosheets for highly efficient hydrogen evolution and Zn-H_(2)O battery

摘要

Thanks to tunable physical and chemical properties,two-dimensional(2D)materials have received intensive interest,endowing their excellent electrocatalytic performances for applications in energy conversion.However,their catalytic activities are largely determined by poor adsorption energy and limited active edge sites.Herein,a one-step electrochemical exfoliation strategy was developed to fabricate 2D Ni-doped MoS_(2)nanosheets(Ni-EX-MoS_(2))with a lateral size of500 nm and thickness of3.5 nm.Profiting from high electrical conductivity and abundant exposing active sites,Ni-EX-MoS_(2)catalyst displayed an admirable performance for electrochemical hydrogen evolution reaction(HER)with a low overpotential of 145 m V at 10 m A/cm^(2)as well as a small Tafel slope of 89 m V/dec in alkaline media,which are superior to those of the most reported MoS_(2)-based electrocatalysts.The formed Ni species with tuning electronic structure played a crucial role as primary active center of Ni-EX-MoS_(2),as well as the forming stable 1T/2H phase MoS_(2)interface demonstrated a synergistic effect on electrocatalytic HER performance.Further,Ni-EX-MoS_(2)was employed as a cathode electrode for alkaline Zn-H_(2)O battery,which displayed a high power density of 3.3 m W/cm^(2)with excellent stability.This work will provide a simple and effective guideline for design of electrochemically exfoliated transition metal-doped MoS_(2)nanosheets to inspire their practical applications in energy catalytic and storage.