Investigation of Ag–ZnO/rGO Hybrid Composite Material as a Photocatalyst for Phenol Degradation in Aqueous Systems

This study aims to enhance the photocatalytic degradation of phenol under UV light by synthesizing a silver-zinc oxide/reduced graphene oxide (Ag-ZnO/rGO) hybrid composite via a hydrothermal method. Structural and optical characterizations confirmed the successful incorporation of Ag and rGO into the ZnO matrix, leading to improved light absorption and efficient charge separation. Photocatalytic tests revealed that the Ag-ZnO/rGO hybrid composite showed superior activity, degrading 76.16% of phenol in just 12 h, significantly higher than Ag-ZnO (65.66%) and pure ZnO (31.78%). After 24 h, it achieved 98.91% degradation. Kinetic analysis confirmed its enhanced performance, showing the highest pseudo-first-order rate constant (<i>k</i> = 0.1883 h^-1) among all samples. This improvement is attributed to the synergistic effects of Ag and rGO, which promote efficient charge separation and faster degradation kinetics. The enhanced photocatalytic efficiency is attributed to the surface plasmon resonance (SPR) effect of Ag nanoparticles (NPs) and the excellent electron transport properties of rGO, which collectively suppress charge carrier recombination. These findings highlight the promising potential of Ag-ZnO/rGO as a high-performance photocatalyst for environmental remediation and wastewater treatment applications.