Construction of Ag SPR-promoted Z-scheme Ag2MoO4/CuBi2O4 composites with enhanced photocatalytic performance

Recently, the photocatalytic oxidation technique for removing antibiotics and industrial dyes in wastewaters has attracted widespread concern. Herein, a Z-scheme Ag2MoO4/CuBi2O4 heterojunction was synthesized by utilizing a facile in situ precipitation medium and characterized by XRD, FT-IR, XPS, FE-SEM, EDS, TEM, UV-Vis DRS, PL and photoelectrochemical test for explaining the compositions, morphologies and optical natures of synthesized catalysts. Most importantly, the size of the Ag2MoO4 is significantly reduced after loading, due to the pre-adsorption of Ag ions on the CuBi2O4 rod and limiting its growth. The best photocatalytic degradation property was achieved when introducing similar to 50% moral of Ag2MoO4 in the Ag2MoO4/CuBi2O4 (AC-50), and the degradation efficiency of tetracycline (TC) and rhodamine B (RhB) was 1.84 times and 2.04 times than that of pristine CuBi2O4. Besides, the reduction of silver nanoparticles (NPs) on the surface of Ag2MoO4/CuBi2O4 during photodegradation contributes to the formation of the Z-scheme Ag2MoO4/Ag/CuBi2O4 charge transfer system. Tapping tests and ESR analysis had proved that superoxide radicals (center dot O-2(-)) and holes (h(+)) were the governing active substances during the process of photodegradation. In view of characterization results and capture tests, a plasma Z-scheme Ag2MoO4/Ag/CuBi2O4 heterojunction mechanism is further described, which provides more redox species and contributes to water pollution repair treatments.