Successive photocatalytic degradation of methylene blue by CuO, Fe2O3, and novel nanocomposite CuO/Fe2O3 synthesized from Mentha pulegium plant extract via biosynthesis technique

The demand for environmentally friendly and sustainable materials has raised awareness of bio-reinforced nanocomposites. Using the green synthesis technique and Mentha pulegium extract as a reducing agent, a novel CuO/Fe2O3 nanocomposite was developed. The structural and optical properties of CuO/Fe2O3 nanocomposite were investigated using X-ray diffraction (XRD), UV-visible, and Fourier-transform infrared (FTIR) spectroscopies. The obtained CuO/Fe2O3 nanocomposite exhibits absorption at 290 nm with a direct bandgap ranging from 4.73 to 5.06 eV and an indirect bandgap of 2.60 to 2.90 eV, according to UV-visible spectra. FTIR analysis exhibits appearance three peaks at 566, 485, and 467 cm(-1) attributed to the CuO NPs, Fe2O3 NPs, and CuO/Fe2O3 nanocomposites binding of iron and copper(II) chloride. The produced nanoparticles formed a hexagonal and monoclinic crystal structure with a crystallite size of approximately 22.93 nm, according to X-ray diffraction (XRD) research results. By using visible and UV-vis spectroscopy, the catalytic activity of produced CuO/Fe2O3 in the breakdown of methylene blue (MB) dye was investigated, and the results were compared to the catalytic activity of CuO and Fe2O3 NPs. The decolorization ratios of dye for CuO/Fe2O3 nanocomposite were 99.52% within 120 min, while CuO and Fe2O3 NPs reduced by 62.15% and 74.83%, respectively. The present research highlights the importance of metallic nanocomposite produced by green synthesis for industrial applications.