Promoting the charge separation and photoelectrocatalytic water reduction kinetics of Cu_(2)O nanowires via decorating dual-cocatalysts

摘要

Developing high activity and low-cost materials to produce hydrogen by the sustainable way of photoelectrochemical is key to social development.The abundance and inexpensive Cu_(2)O has been received increasing research as its suitable energy level for photocatalytic water reduction.However,the fast charge recombination rate and the sluggish catalytic kinetics are the huge challenges facing the Cu_(2)O photoreduction.Here,the highly reactive Cu_(2)O@C-MoS_(2)photocathode is constructed by depositing dual-cocatalysts of the carbon layer and MoS_(2)nanosheets on Cu_(2)O nanowires to realize efficient water reduction.An impressive carrier concentration of 6.59×10^(23)cm^(-3)is received,which is 2.78 times of the bare Cu_(2)O,resulting in remarkable enhancement in photocurrent density of 3.34 times for the Cu_(2)O@CMoS_(2)photocathode.Moreover,the applied bias photon-to-current conversion efficiency of the bare Cu_(2)O enhanced 4.5 times from 0.16%to 0.72%in the Cu_(2)O@C-MoS_(2)photocathode.The analysis shows that the Cu_(2)O as light absorber,the carbon layer as electron transfer promoter,and MoS_(2)nanosheets as catalytic sites,thus facilitating chrage separation and enhancing catalytic kinetics.This system paves a feasible strategy for designing other photoelectrodes to realize efficient charge separation and high catalytic activity.