One-pot Synthesis of CdS Irregular Nanospheres Hybridized with Oxygen-Incorporated Defect-Rich MoS2 Ultrathin Nanosheets for Efficient Photocatalytic Hydrogen Evolution

5 years ago

One-pot Synthesis of CdS Irregular Nanospheres Hybridized with Oxygen-Incorporated Defect-Rich MoS2 Ultrathin Nanosheets for Efficient Photocatalytic Hydrogen Evolution

Jinzhao Huang, Xijin Xu, Ruya Cao, Shouwei Zhang, Huihui Gao, Hongcen Yang

Robust and highly active photocatalysts, CdS@MoS₂, for hydrogen evolution were successfully fabricated by one-step growth of oxygen-incorporated defect-rich MoS₂ ultrathin nanosheets on the surfaces of CdS with irregular fissures. Under optimized experimental conditions, the CdS@MoS₂ displayed a quantum yield of ∼24.2% at 420 nm and the maximum H₂ generation rate of ∼17203.7 umol/g/h using Na₂S–Na₂SO₃ as sacrificial agents (λ ≥ 420 nm), which is ∼47.3 and 14.7 times higher than CdS (∼363.8 μmol/g/h) and 3 wt % Pt/CdS (∼1173.2 μmol/g/h), respectively, and far exceeds all previous hydrogen evolution reaction photocatalysts with MoS₂ as co-catalysts using Na₂S–Na₂SO₃ as sacrificial agents. Large volumes of hydrogen bubbles were generated within only 2 s as the photocatalysis started, as demonstrated by the photocatalytic video. The high hydrogen evolution activity is attributed to several merits: (1) the intimate heterojunctions formed between the MoS₂ and CdS can effectively enhance the charge transfer ability and retard the recombination of electron–hole pairs; and (2) the defects in the MoS₂ provide additional active S atoms on the exposed edge sites, and the incorporation of O reduces the energy barrier for H₂ evolution and increases the electric conductivity of the MoS₂. Considering its low cost and high efficiency, this highly efficient hybrid photocatalysts would have great potential in energy-generation and environment-restoration fields.

Publisher URL: http://dx.doi.org/10.1021/acsami.7b03673

DOI: 10.1021/acsami.7b03673