Plasmonic Ag‑Decorated Few‑Layer MoS2 Nanosheets Vertically Grown on Graphene for Efficient Photoelectrochemical Water Splitting

摘要

A controllable approach that combines surface plasmon resonance and twodimensional(2D)graphene/MoS2 heterojunction has not been implemented despite its potential for efficient photoelectrochemical(PEC)water splitting.In this study,plasmonic Ag-decorated 2D MoS2 nanosheets were vertically grown on graphene substrates in a practical large-scale manner through metalorganic chemical vapor deposition of MoS2 and thermal evaporation of Ag.The plasmonic Ag-decorated MoS2 nanosheets on graphene yielded up to 10 times higher photo-to-dark current ratio than MoS2 nanosheets on indium tin oxide.The significantly enhanced PEC activity could be attributed to the synergetic effects of SPR and favorable graphene/2D MoS2 heterojunction.Plasmonic Ag nanoparticles not only increased visible-light and near-infrared absorption of 2D MoS2,but also induced highly amplified local electric field intensity in 2D MoS2.In addition,the vertically aligned 2D MoS2 on graphene acted as a desirable heterostructure for efficient separation and transportation of photo-generated carriers.This study provides a promising path for exploiting the full potential of 2D MoS2 for practical large-scale and efficient PEC water-splitting applications.