Ag nanoparticles-embellished Bi12GeO20 composites: A plasmonic system featured with reinforced visible-light photocatalytic performance and ultra-stability

In this study, various plasmonic binary composites Ag-Bi12GeO20 were fabricated through a facile in-situ photoreduction route and subsequently analyzed by multitudinous techniques. The presence of both desirable ingredients in heterojunction structures were confirmed by XPS, SEM, TEM, and EDS elemental mapping and band structures were analyzed by UV-Vis DRS spectra. Moreover, steady-state and transient PL and electrochemical spectra were recorded to reveal effective spatial separation of charge carriers. The effective separation of charge carriers, reinforced visible-light absorption by local surface plasmon resonance effect of Ag nanoparticles, appropriate phase composition, and enlarged specific surface areas contributed to enhanced catalytic degradation of organic dye RhB and antibiotic TC and reduction of Cr (VI) under visible light. Specifically, the best candidate 1AB exhibited apparent reaction rate constants over degradation of RhB and TC and reduction of Cr (VI) about 5.0, 1.72, and 5.77 times those of bare Bi12GeO20 under the identical condition. In addition, basing on experimental and electrochemical analyses a possible photocatalysis mechanism was speculated for these robust and recyclable plasmonic binary composites. Such investigation would provide a novel alternative plasmonic system for environmental protection and mediation by means of photocatalytic technology.