Sustainable synthesis and photocatalytic insights into Ag-doped copper oxide nanoparticles: a comparative study

The fabrication of silver (Ag)-doped copper oxide (CuO) nanoparticles has attracted significant interest because of their improved photocatalytic efficiency and promising applications in environmental remediation. This study provides a comparative analysis of Ag-doped CuO nanoparticles synthesized through two different approaches: a conventional chemical method and a green synthesis route utilizing Moringa oleifera leaf extract as a natural reducing and stabilizing agent. The structural, morphological, and optical characteristics of the synthesized nanoparticles were examined using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), and photoluminescence (PL) spectroscopy. The photocatalytic performance of Ag-doped CuO nanoparticles was assessed by degrading organic pollutants under visible light irradiation. The findings revealed that Ag doping notably enhanced charge carrier separation, minimized electron-hole recombination, and improved visible-light absorption, attributed to localized surface plasmon resonance (LSPR) effects. The green-synthesized Ag-CuO nanoparticles exhibited superior stability and photocatalytic efficiency, attributed to their smaller crystallite size, reduced agglomeration, and bio-organic capping provided by Moringa oleifera phytochemicals, which enhance surface reactivity and visible-light absorption, highlighting the advantages of sustainable, eco-friendly approaches in nanomaterial synthesis. The study provides valuable insights into the influence of synthesis methods on the physicochemical as well as photocatalytic properties of CuO nanocomposites doped with Ag, paving the way for their potential applications in wastewater treatment, antimicrobial coatings, and advanced photocatalytic systems.