Facile fabrication of ternary metal oxide ZnO/CuO/SnO2 nanocomposite for excellent photocatalytic degradation of fast green dye

Abstract

ABSTRACT The uncontrolled release of hazardous dyes from textile industries without any pre-treatment has resulted in severe aquatic environment contamination. Owing to their complex aromatic structures, these dyes remain in the water bodies for longer periods. To eradicate toxic dyes from the aquatic ecosystem, there is an immense need to develop advanced scientific approaches. Here, we report the synthesis of a novel ternary metal oxide nanocomposite, ZnO/CuO/SnO2, having high photocatalytic activity. The ZnO/CuO/SnO2 nanocomposite characterisation was done by XRD, FT-IR, UV-Vis, PL, TGA, FE-SEM, TEM, and BET techniques. The composition of the nanocomposite was investigated by XRD analysis, which revealed the presence of three oxide components. The optical properties such as bandgap, were calculated from UV–Vis absorbance data using the Butler equation. The observed bandgap for zinc oxide (ZnO), copper oxide (CuO), tin oxide (SnO2), and ZnO/CuO/SnO2 was noticed as 3.18 eV, 1.3 eV, 3.5 eV, and 2.0 eV, respectively. The ZnO/CuO/SnO2 nanocomposite was applied to degrade the fast green dye under visible light irradiation and exhibited 93.68% degradation efficiency within a short period. Radical trapping experiments were performed to understand the photocatalytic mechanism, superoxide and holes were revealed as the main reacting species. Lastly, the composite catalyst showed excellent photostability with significant retention of photocatalytic efficiency even after four catalytic cycles.