Effect of Musa acuminata peel extract on synthesis of ZnO/CuO nanocomposites for photocatalytic degradation of methylene blue

ABSTRACT The photocatalytic degradation of the organic pollutants using the green synthesized catalysts is an environmentally safe approach for the wastewater treatment. In this study, ZnO and CuO nanoparticles (NPs) and ZnO/CuO nanocomposites (NCs) with various CuO weight percents were synthesized using extract of Musa acuminata fruit peel as the stablizing and capping agent. The synthesized nanomaterials were characterized by TGA/DTA, XRD, SEM, TEM, SAED, HR-TEM, UV-DRS and FTIR techniques. The degradation of methylene blue (MB) dye using the synthesized catalysts was investigated under a visible light source. XRD analysed average crystalline sizes were 24.9, 17.0 and 22.6 nm for ZnO, CuO, and ZnO/CuO nanomaterials, respectively. The SEM and TEM analysis confirms that ZnO NPs, CuO NPs, and ZnO/CuO NCs possessed the spherically shaped monoclinic structure. The bandgap energies of ZnO NPs, CuO NPs and ZnO/CuO NCs were found to be 3.25, 1.7 and 3.18 eV respectively. The FT-IR analysis confirms presence of various reducing and capping agents. The photocatalytic activities of ZnO NPs, CuO NPs, and ZnO/CuO NCs were evaluated using the degradation of MB dye under the visible light irradiation. The photocatalysts CuO, ZnO, and ZnO/CuO exhibited the degradation efficiencies of 50%, 57%, and 90%, respectively. GRAPHICAL ABSTRACT