La, Zr co-doped Ag3PO4 for enhanced visible-light photocatalytic degradation of dyes and Cr(VI) photoreduction

Visible light-driven photocatalysts have attracted considerable attention as these photocatalysts can effectively utilize visible light and are cost-effective. This study reports the synthesis of silver phosphate (Ag3PO4) and 1, 3, and 5% La, Zr co-doped Ag3PO4 via precipitation method. The synthesized materials were characterized using powder X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), UV-Visible diffuse reflectance spectra (DRS), photoluminescence spectroscopy (PL), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX). No impurities were observed in all the synthesized materials as shown by the XRD analysis. FTIR measurements of the synthesized materials displayed the presence of several functional groups in the synthesized materials. The band gap energy of Ag3PO4 decreases as more La and Zr were incorporated into the Ag3PO4 lattice. The SEM images of Ag3PO4 displayed tetrapod-shaped particles whereas La, Zr co-doped Ag3PO4 showed irregular particles. The photocatalytic activities of the synthesized materials were determined through photocatalytic degradation of methylene blue (MB) and methyl orange (MO) dyes as well as photoreduction of Cr(VI). Results showed that 1% La, Zr co-doped Ag3PO4 exhibited superior photocatalytic properties in both photocatalytic processes when compared to Ag3PO4.