Highly efficient photocatalytic activity of Ag3VO4/WO2.72 nanocomposites for the degradation of organic dyes from the ultraviolet to near-infrared regions

Full-spectrum light-driven Ag3VO4/WO2.(7)(2) nanocomposites were prepared using a simple precipitation method. The nanocomposites were characterized via X-ray diffraction (XRD) analysis, field-emission scanning electron microscopy (FE-SEM), ultraviolet-visible (UV-Vis) spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), photoluminescence (PL) spectroscopy, Brunauer-Emmett-Teller (BET) analysis, and electrochemical impedance spectroscopy (EIS). The photocatalytic performance of the nano-composites for the photodegradation of methylene blue (MB) and Rhodamine B (Rh B) were examined. The Ag3VO4/WO2.72 nanocomposites exhibited outstanding photocatalytic performance for the photodegradation of Rh B and MB, and they were stable under irradiation with UV, visible, near-infrared (NIR), and solar light. A nanocomposite prepared with Ag3VO4 and WO2.72 in a 1:2 M ratio (AgV-WO-2) exhibited particularly high photodegradation efficiency. AgV-WO-2 photodegraded 99% of the Rh B and 98% of the MB in aqueous solutions under solar and visible light. Under UV light, 96% of the Rh B and 89% of the MB were degraded, while 40% of the Rh B and 38% of the MB in solutions irradiated with NIR light were removed. The photocatalytic performance of the nanocomposites for the photoreduction of chromium (VI) was also studied. AgV-WO-2 exhibited a photoreduction efficiency of 90% under solar light irradiation. The activities of the AgV-WO-2 nanocomposite for the photodegradation of Rh B and the photoreduction of Cr (VI) were compared to those reported for other catalysts. The photocatalytic activity of the Ag3VO4/WO2.72 nanocomposite was better. It is thus a promising photocatalyst for the removal of Rh B, MB, and chromium (VI).