Highly efficient visible-light-driven photocatalytic hydrogen evolution by all-solid-state Z-scheme CdS/QDs/ZnIn2S4 architectures with MoS2 quantum dots as solid-state electron mediator

Abstract

All-solid-state Z-scheme CdS/QDs/ZnIn2S4 architectures with MoS2 quantum dots as solid-state electron mediator were successfully designed and constructed by optimally combining one-dimensional CdS nanorods, zero-dimensional MoS2 quantum dots (QDs) and two-dimensional ZnIn2S4 nanosheets. The photocatalytic water splitting for hydrogen evolution demonstrated that such structural design can synergistically trigger remarkably improved visible-light-driven photocatalytic activity. Photocatalytic H2-evolution at 2107.5 μmol g−1 h−1 was achieved on this CdS/QDs/ZnIn2S4 architectures under visible light irradiation, exceeding those of bare CdS nanorods and pure ZnIn2S4 nanosheets by a factor of 26 and 62, respectively. This highly efficient photocatalytic activity arises from the effective charge separation and favourable electron mediator of MoS2 QDs. The Z-scheme charge separation mechanism was verified by the ESR, PL-TA and organic electron acceptor test.