Photocatalytic degradation of metronidazole (MNZ) antibiotic by CuO nanoparticles for environmental protection from pharmaceutical pollution

Metronidazole (MNZ) is one of the extensively consumed generic antibiotics, which, due to its high resistance to biological degradation, is considered a potent environmental contaminant. In this study, we use CuO nanoparticles (NPs) for photocatalytic degradation of MNZ. Photocatalytic NPs with a crystallinity of over 80% were synthesized using a facile co-precipitation method followed by calcination at a temperature of 500°C for a duration of 1 h. NPs were characterized thoroughly to investigate their opto-structural properties. We investigated the efficiency of photocatalytic degradation with the variation of MNZ concentration, NP loading and the pH of the MNZ solution. Experimental results revealed that the pH of the MNZ solution strongly controlled the photocatalytic degradation efficiency. As pH was increased from 7 to 11, the degradation rate was enhanced remarkably. Degradation efficiency was also found to be strongly dependent on the concentration of both MNZ solution and CuO NPs.