Constructing S-scheme heterojunction of octahedral flower-like ZnIn2S4/Bi2WO6 nanocone with enhanced photocatalytic activity

Abstract

In this study, we fabricated octahedral flower-like ZnIn2S4/Bi2WO6 (ZIS/BWO) composite photocatalysts employing octahedral Bi2WO6 nanocones and sheet ZnIn2S4 by in-situ growth method. The synthesized composites were characterized by high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray powder diffraction (XRD), respectively. It can be observed that ZnIn2S4 nanosheets grows from the surface of the Bi2WO6 nanocone to form octahedral flower-like ZIS/BWO nanocone composite photocatalysts. The prepared ZIS/BWO composite photocatalysts are speculated that it conforms to the S-scheme heterojunction by UV–vis diffuse reflectance spectra (UV-DRS) and electrochemical analyses combing with the redox potential of reactive oxygen species. The S-scheme heterojunction of ZIS/BWO composite photocatalysts exhibits good separation and transportation of photogenerated carriers by photocurrent and photoluminescence (PL). In addition, the ZIS/BWO composites with S-scheme heterojunction enhances photocatalytic degradation Rhodamine B (RhB), which still showed good photocatalytic activity (62.4%) after four consecutive cycles of photodegradation experiments. This S-scheme heterojunction of the unique structure will be potential and promising photocatalytic catalysts for environmental purification and energy conversion in the coming years.