Sutherlendia frutescence-Mediated CuNiO Nanocomposite: Effect of Varying Loadings on the Degradation of Pharmaceutical Pollutants and Antibacterial Efficiency

Abstract

Water contamination with pharmaceuticals is a global challenge that affects both aquatic and human life. The presence of these pharmaceuticals has increased in recent years due to their high demand. In this study, varying compositions of Cu-NiO nanocomposites were synthesized using Sutherlandia frutescens plant extracts. The synthesized nanoparticles were characterized using UV–vis, FTIR, XRD, SEM, EDS and TGA. The photocatalytic activity of these materials was tested on SMX and CIP antibiotics. Furthermore, their antibacterial efficiency against Gram-negative and Gram-positive bacterial strains was investigated. XRD, through phase identification and SEM/EDS, confirmed the formation of nanocomposites with elements of Cu, O and Ni. The 15% CuNiO nanocomposite demonstrated the highest thermal stability with a minimal weight loss of 3%. The 15% CuNiO had the highest degradation efficiencies of 92% and 85% for SMX and CIP, respectively. The catalyst could be reusable for up to three trials with a 65% efficiency against CIP, while the photogenerated electrons (e−) were the most reactive species for the degradation of pharmaceuticals. Lastly, these materials were noted to have antibacterial efficiency against both Gram-negative and -positive strains, with the highest zone of inhibition against E. coli. This study has shown that novel green nanocomposites from S. frutescence can be used for targeting multiple pollutants simultaneously by degrading antibiotics efficiently and removing various bacterial strains.