MoS2/WS2 heterojunction for photoelectrochemical water oxidation
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
The solar-assisted oxidation of water is an essential half reaction for achieving a complete cycle of water splitting. The search of efficient photoanodes that can absorb light in the visible range is of paramount importance to enable cost-effective solar energy-conversion systems. Here, we demonstrate that atomically thin layers of MoS2 and WS2 can oxidize water to O2 under incident light. Thin films of solution-processed MoS2 and WS2 nanosheets display n-type positive photocurrent densities of 0.45 mA cm–2 and O2 evolution under simulated solar irradiation. WS2 is significantly more efficient than MoS2; however, bulk heterojunctions (B-HJs) of MoS2 and WS2 nanosheets results in a 10-fold increase in incident-photon-to-current-efficiency, compared to the individual constituents. This proves that charge carrier lifetime is tailorable in atomically thin crystals by creating heterojunctions of different compositions and architectures. Our results suggest that the MoS2 and WS2 nanosheets and their B-HJ blend are interesting photocatalytic systems for water oxidation, which can be coupled with different reduction processes for solar-fuel production.
Date Issued
2017-08-04
Date Acceptance
2017-06-22
Citation
ACS Catalysis, 2017, 7 (8), pp.4990-4998
ISSN
2155-5435
Publisher
American Chemical Society
Start Page
4990
End Page
4998
Journal / Book Title
ACS Catalysis
Volume
7
Issue
8
Copyright Statement
© 2017 American Chemical Society
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Imperial College London
Grant Number
EP/M022250/1
EP/K01658X/1
EP/K016792/1
EP/L003481/1
EP/K033840/1
Subjects
Science & Technology
Physical Sciences
Chemistry, Physical
Chemistry
photoanode
water splitting
heterojunction
MoS2
WS2
LAYER
HETEROSTRUCTURES
NANOSHEETS
EVOLUTION
MONO
PHOTOLUMINESCENCE
PHOTOOXIDATION
RECOMBINATION
PHOTOANODES
0302 Inorganic Chemistry
0305 Organic Chemistry
0904 Chemical Engineering
Publication Status
Published
Date Publish Online
2017-06-22