Insight into the relationship of the high photocatalytic performance and double photochromic activity of Z-scheme CsxWO3/AgBr heterostructures under UV-Vis-NIR light utilization

Effective and suitable utilization of solar energy was achieved using a full-spectrum-response photocatalyst AgBr/CsxWO3, applied in the photocatalytic and photochromic field. Benefitting from near-infrared (NIR) absorption ability of CsxWO3, AgBr/CsxWO3 exhibits enhanced visible-near-infrared (Vis-NIR) driven photocatalytic activity. Based on X-ray photoelectron spectroscopy (XPS), photoluminescence spectra (PL), and the photoelectrochemical analysis, AgBr and CsxWO3 formed a Z-scheme system at the interface to efficiently separate and transfer photo-induced electrons at a fast rate. The quenching experiment and the electron spin resonance (ESR) tests indicated that the photocatalytic reaction is activated by the production of superoxide radicals. Furthermore, the photochromic analysis to different light exhibits the AgBr/CsxWO3 heterostructure is stable under visible light with negligible photodeposition of AgBr, and has excellent double photochromic activity with visible-shielding effect of AgBr to Ag-0 and infrared-blocking effect of CsxWO3 under ultraviolet light. This research provides new insights into the manufacture of energy-efficient and environmentally friendly materials that provide excellent performance in both thermal insulation and decontamination.