Construction of S-scheme Mn0.1Cd0.9S/WO3 1D/0D heterojunction assemblies for visible-light driven high-efficient H2 evolution

Abstract

Metal chalcogenides still suffer from the fast recombination of photoinduced charges and serious photo-corrosion when used as visible-light-responsive photocatalysts. The rationally designed photocatalysts should simultaneously possess high light-harvesting efficiency, fast charge separation, optimum redox ability and lasting stability, and this remains a big challenge. Herein, 0D WO3 nanoparticles (NPs) were prepared by using a deep eutectic solvents (DESs) pyrolysis method. And then 0D WO3 NPs coupled 1D Mn0.1Cd0.9S (MCS) nanorods were introduced to construct the S-scheme 1D/0D MCS/W heterojunction cauliflower-shaped assemblies, which were developed by using a simple hydrothermal method. X-ray photoelectron spectra disclosed the formation of the S-W-O bond, indicating strong interfacial interaction between MCS and WO3 at the heterojunction. The formed S-scheme 1D/0D MCS/W heterojunction cauliflower-shaped assemblies and the construction of internal electric field not only enhance visible light absorption, but also boost charge separation efficiency, and endow higher redox ability and long-term durability. Profiting from morphological and energy band structure synergy, the resultant MCS/W heterojunction assemblies exhibited an enhanced photocatalytic H2 generation rate of 21.25 mmol h−1 g−1, which was 25 times higher than that of pristine MCS. This work provides new deep insights into the rational construction of S-scheme heterojunction assemblies based on morphology and band structure design to boost the photocatalytic performance.