Open AccessA Ternary Dumbbell Structure with Spatially Separated Catalytic Sites for Photocatalytic Overall Water Splitting
Author(s) -
Qiu Bocheng,
Cai Lejuan,
Zhang Ning,
Tao Xiaoming,
Chai Yang
Publication year - 2020
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201903568
Subject(s) - water splitting , dumbbell , ternary operation , photocatalysis , catalysis , oxygen evolution , materials science , photocatalytic water splitting , sulfide , hydrogen , chemical engineering , chemical physics , photochemistry , chemistry , medicine , biochemistry , organic chemistry , electrode , computer science , engineering , metallurgy , electrochemistry , programming language , physical therapy
Solar‐driven overall water splitting based on metal sulfide semiconductor photocatalysts remains as a challenge owing to the strong charge recombination and deficient catalytic active sites. Additionally, significant inhibition of back reactions, especially the oxidation of sulfide ions during the photocatalytic water oxidation catalysis, is an arduous task that requires an efficient photogenerated hole transfer dynamics. Here, a ternary dumbbell‐shaped catalyst based on RuO 2 /CdS/MoS 2 with spatially separated catalytic sites is developed to achieve simultaneous production of hydrogen and oxygen under simulated solar‐light without any sacrificial agents. Particularly, MoS 2 nanosheets anchored on the two ends of CdS nanowires are identified as a reduction cocatalyst to accelerate hydrogen evolution, while RuO 2 nanoparticles as an oxidation cocatalyst are deposited onto the sidewalls of CdS nanowires to facilitate oxygen evolution kinetics. The density functional theory simulations and ultrafast spectroscopic results reveal that photogenerated electrons and holes directionally migrate to MoS 2 and RuO 2 catalytic sites, respectively, thus achieving efficient charge carrier separation. The design of ternary dumbbell structure guarantees metal sulfides against photocorrosion and thus extends their range in solar water splitting.