Superior photocatalytic activity of bimetallic Cd-Ag-ZnO for the degradation of azo dyes under UV light

Development of bimetallic semiconductor oxides with synergistic functions makes a significant advancement in catalytic technologies. This study addresses the preparation of a codoped bimetallic Cd-Ag-ZnO photocatalyst by solvothermal process and its characterization by x-ray diffraction (XRD), high-resolution scanning electron microscopy (HR-SEM), UV-Vis diffuse reflectance spectroscopy (DRS), energy dispersive spectroscopy (EDS), and photoluminescence spectroscopy (PL). XRD and EDS reveal the presence of Cd and Ag in the catalyst. HR-SEM images show plate-like structure of ZnO and the clusters of Cd and Ag on the surface ZnO. Cd-Ag-ZnO has increased absorption in the UV region. This bimetalic photocatalyst shows higher photocatalytic activity for the degradation of Acid Black 1 (AB 1) and Acid Violet 7 (AV 7) under UV light (365 nm) than pure ZnO and commercial TiO₂-P25. Cd-Ag-ZnO was found to be stable and reusable without appreciable loss of catalytic activity up to three runs.