Ultra-thin nanosheet assembled 3D honeycomb-like Zn0.5Cd0.5S for boosting photocatalytic H2 evolution

Designing photocatalysts with excellent morphology from MOF is a promising strategy to improve photocatalytic H2 evolution. Herein, a three-dimensional (3D) honeycomb-like Zn0.5Cd0.5S-140 assembled by ultra-thin nanosheets with an average thickness of about 1.5 nm was constructed using a novel 3D metal-organic framework (namely PZH-139) as template. Notably, the micromorphology could be tuned and the balance between conduction band (CB) position and band gap could achieve by adjusting the Zn/Cd molar ratio of ZnxCd1-xS. In a series of ZnxCd1-xS-140 photocatalysts derived from MOF, Zn0.5Cd0.5S-140 exhibited the highest hydrogen evolution rate (26.32 mmol h-1 g-1) by visible-light-driven with an apparent quantum efficiency (AQE) of 29.92 %, which was 6, 11 and 23 times higher than that of I-Zn0.5Cd0.5S (irregular morphology Zn0.5Cd0.5S), S-Zn0.5Cd0.5S (spherical Zn0.5Cd0.5S) and B-Zn0.5Cd0.5S (bulk Zn0.5Cd0.5S) prepared by traditional non-MOFs derived-methods, respectively. The excellent photocatalytic performance could be attributed to the synergism of the larger specific surface area, the balance between CB position and band gap, rapid carriers transfer and the enhanced light absorption capability. More importantly, this rare strategy for constructing highly efficient ultra-thin nanosheet assembled 3D honeycomb-like Zn0.5Cd0.5S-140 derived from MOF can flourish the design ideas of photocatalysts with specific excellent morphology.

Automated summary

Designing photocatalysts with excellent morphology from MOF is a promising strategy to improve photocatalytic H2 evolution. In this study, a 3D honeycomb-like Zn0.5Cd0.5S-140 assembled by ultra-thin nanosheets was constructed using a novel MOF template. The Zn0.5Cd0.5S-140 photocatalyst exhibited the highest hydrogen evolution rate and apparent quantum efficiency among the ZnxCd1-xS-140 photocatalysts derived from MOF.