Insight on the plasmonic Z-scheme mechanism underlying the highly efficient photocatalytic activity of silver molybdate/silver vanadate composite in rhodamine B degradation.

A facile deposition-precipitation method was applied to synthesize novel plasmonic Z-scheme AgMoO/AgVO photocatalysts with different molar ratios of AgMoO. The morphological, structural, and spectroscopic properties of the as-obtained samples were characterized through X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectral analysis. The photocatalytic performance of the synthesized photocatalysts in rhodamine B (RhB) degradation under visible light irradiation was evaluated. The 5% AgMoO/AgVO composite displayed the highest photocatalytic activity among all samples and the RhB removal rate of 93% within 6 min. The RhB removal rate of 5% AgMoO/AgVO composite was higher than that of precursor AgMoO and AgVO compounds. The formation of Ag nanoparticles (Ag NPs) on the surface of AgMoO/AgVO during photocatalysis resulted in the transformation of the AgMoO/AgVO heterojunction to the AgMoO/Ag/AgVO Z-scheme system, thus enhancing photocatalytic activity. Z-scheme AgMoO/Ag/AgVO composites could efficiently facilitate charge transfer, promote redox ability, and restrain AgVO photocorrosion. The produced active species O, h, and OH are vital for RhB degradation. The present work could benefit the development of advanced visible-light photocatalytic materials with future applications in environmental remediation.