title: Efficient photoelectrochemical hydrogen generation using heterostructures of Si and chemically exfoliated metallic MoS2.
abstract: We report the preparation and characterization of highly efficient and robust photocathodes based on heterostructures of chemically exfoliated metallic 1T-MoS2 and planar p-type Si for solar-driven hydrogen production. Photocurrents up to 17.6 mA/cm(2) at 0 V vs reversible hydrogen electrode were achieved under simulated 1 sun irradiation, and excellent stability was demonstrated over long-term operation. Electrochemical impedance spectroscopy revealed low charge-transfer resistances at the semiconductor/catalyst and catalyst/electrolyte interfaces, and surface photoresponse measurements also demonstrated slow carrier recombination dynamics and consequently efficient charge carrier separation, providing further evidence for the superior performance. Our results suggest that chemically exfoliated 1T-MoS2/Si heterostructures are promising earth-abundant alternatives to photocathodes based on noble metal catalysts for solar-driven hydrogen production.
authors.affiliation: Department of Chemistry, University of Wisconsin - Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
authors.forename: Qi
authors.initials: Q
authors.lastname: Ding
authors.forename: Fei
authors.initials: F
authors.lastname: Meng
authors.forename: Caroline R
authors.initials: CR
authors.lastname: English
authors.forename: Miguel
authors.initials: M
authors.lastname: Cabán-Acevedo
authors.forename: Melinda J
authors.initials: MJ
authors.lastname: Shearer
authors.forename: Dong
authors.initials: D
authors.lastname: Liang
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Daniel
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Hamers
authors.forename: Song
authors.initials: S
authors.lastname: Jin