Photocatalytic removal of aldrin and dieldrin using graphene oxide and TiO2-doped CuFe2O4

BACKGROUND Conventional treatment processes and existing photocatalysts have proven insufficient in efficiently removing aldrin and dieldrin. Consequently, this study aimed to investigate the removal of aldrin and dieldrin from surface water using a titanium dioxide/graphene oxide/copper ferrite (TiO2/GO/CuFe2O4) nanocomposite. RESULTS The highest photodegradation efficiencies for aldrin (100%) and dieldrin (99%) were achieved with a TiO2/GO/CuFe2O4 nanocomposite dosage of 1.3 mg L-1, at a sunlight intensity of 9 W m(-2) and an optimal photodegradation time of 25 min. The maximum UV absorption wavelength of the TiO2/GO/CuFe2O4 nanocomposite was observed at 365 nm. The quantum yield of the nanocomposite was recorded as 2.69 x 10(2) mol einstein-1, and its bandgap energy was determined to be 3.31 eV. The first-order kinetic rate constants for aldrin and dieldrin were calculated as 0.05 and 0.047 min(-1), respectively. X-ray diffraction analysis confirmed the crystal structure of CuFe2O4/TiO2, while Fourier transform infrared spectroscopy detected carboxylic, epoxy, carbonyl and other oxygenated groups within the TiO2/GO/CuFe2O4 nanocomposite. Scanning electron microscopy and transmission electron microscopy images revealed that CuFe2O4 was situated on the outer layer of GO. Energy-dispersive X-ray analysis identified the elemental composition of the TiO2/GO/CuFe2O4 nanocomposite as comprising GO, C, Cu, Fe, Ti and O. A reusability study demonstrated that the nanocomposite maintained excellent performance, achieving 99% removal efficiency after 79 cycles and 97% after 100 cycles. CONCLUSIONS The TiO2/GO/CuFe2O4 nanocomposite effectively removed aldrin and dieldrin from surface water. This nanocomposite holds promise for the remediation of other aquatic ecosystems, such as bays, rivers and ocean waters. (c) 2024 The Author(s). Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).