Waste-derived green ZnO–Fe <sub>2</sub> O <sub>3</sub> photocatalyst for degradation of MB dye pollutant in water
Abhijit Nath, Dev K. Mahato, L. Robindro Singh, Probodh K. Kuiri, Mrityunjoy Mahato
Abstract
A green photocatalyst ZnO–Fe2O3 and its polymer composite ball/film were prepared using waste-iron scrap, pea-eggplant, and waste-expanded polystyrene (EPS) for methylene blue (MB) degradation. The optimized bandgap was found to be 2.39 eV by a 1:2 ratio of ZnO (3.11 eV) and Fe2O3(2.05 eV). The heterostructure (average size = 64 nm) was characterized by UV–Vis spectroscopy, XRD, TEM, and its polymer composite was characterized by FTIR. The achieved decolorization percentage of MB dye with visible light using ZnO–Fe2O3 powder, ZnO–Fe2O3–EPS film, and ZnO–Fe2O3–EPS ball are 94.59, 65.71, and 87.49%, respectively. The photocatalysts were found to be reusable up to the 6th cycle with a maximum decolorization of 67.01%. The HR-MS data of the treated solution shows some intermediate fragments. The novelty of the present work lies in the green, waste-derived, and industry-ready stable photocatalyst preparation in the form of powder, film, and ball. The work will give some direction to develop low-cost and industrially relevant visible photocatalysts.