Synthesis of CuO/rGO nanocomposites for carcinogenic Congo red photodegradation

Abstract Removal of carcinogenic Congo red from polluted water is challenging because of its chemical stability and inertness. Here, CuO microsphere assembled rGO nanosheets were successfully fabricated by a simple hydrothermal method for photocatalytic degradation of Congo red. The morphology and microstructure of the CuO/rGO nanocomposites were studied by scanning electron microscopy and X-ray diffraction. The results showed that the produced CuO has a spherical flower like structure that crystallised in the monoclinic crystal phase with a diameter of about 5 μm, combined with thin rGO nanoplates. Fourier transform infrared spectroscopy and Raman spectroscopy confirmed the existence of chemical bonds and vibrational modes of both CuO and rGO. The effect of H2O2 content on the photocatalytic characteristics of as-prepared samples was investigated. The results showed that H2O2 played a key factor in the photocatalytic efficiency. The content of 1 ml H2O2 (30%) exhibited the highest photocatalytic efficiency toward Congo red dye degradation in CuO/rGO (50 mg) under UV light radiation, where it completely removed over 95% Congo red in 100 ml of solution (20 mg L−1) after 120 min of illumination.