High-efficiency new visible light-driven Ag2MoO4–Ag3PO4 composite photocatalyst towards degradation of industrial dyes†
High-efficiency new visible light-driven Ag2MoO4–Ag3PO4 composite photocatalysts with different weight ratios were successfully synthesized by a facile solution-based in situ preparation method and characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV-visible diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence spectroscopy (PL), and zeta potential measurement. Under visible light irradiation, the 10 wt% Ag2MoO4–Ag3PO4 composite photocatalyst exhibits enhanced photocatalytic degradation efficiency compared to other composites of Ag2MoO4–Ag3PO4, pure Ag3PO4 and pure Ag2MoO4 for the degradation of methylene blue (cationic dye). 10 wt% Ag2MoO4–Ag3PO4 composite photocatalyst is further used to investigate the photocatalytic degradation of rhodamine B (cationic dye) and methyl orange (anionic dye). The higher photocatalytic degradation efficiency of 10 wt% Ag2MoO4–Ag3PO4 towards cationic dye is closely related to its surface potential, and the observed degradation efficiency of MB is 2.7 and 16.87 times higher than that of RhB and MO, respectively. Based on the bandgap alignment, the photocatalytic degradation mechanism of Ag2MoO4–Ag3PO4 composite photocatalysts was examined. In addition, the quenching effect of different scavenger tests shows that holes and O2−˙ are the most reactive species which play a major role in photocatalytic degradation of MB. The UV-vis DRS and photoluminescence study also support the higher photocatalytic degradation. TOC analysis was done to confirm the mineralization of dyes. The Ag2MoO4–Ag3PO4 composite photocatalyst is highly stable and 89% MB photocatalytic degradation was achieved after 4 recycle measurements under visible light irradiation. In addition, no phase changes of Ag2MoO4–Ag3PO4 composite photocatalyst and degraded product were confirmed.