One-pot synthesis of an Au modified BiOCOOH plasmonic photocatalyst with enhanced photocatalytic activity

Abstract

In this work, we designed the plasmonic photocatalyst of Au–BiOCOOH through a one-pot method, which can be used to effectively treat wastewater contaminated with rhodamine (RhB) and tetracycline (TC). Compared with neat BiOCOOH, as expected, the resulting Au–BiOCOOH illustrated significantly boosted photocatalytic efficiency for degrading RhB and TC under visible light illumination. Remarkably, 3.0%Au–Bi showed the most optimal performance against RhB and TC, achieving degradation rates of 99.5 % and 99.7 % within 120 min. Through multiple characterization techniques, the physical and chemical photoelectric properties of the photocatalyst as well as the photocatalysis mechanism were discussed in detail. UV–visible diffuse reflectance spectroscopy (DRS) analysis demonstrates that the loading of Au nanoparticles (Au NPs) onto 2D nanosheets of BiOCOOH significantly expanded the wavelength range of response of BiOCOOH to visible light. Separately, the outcomes of electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) manifestly reveal that the presence of Au NPs on BiOCOOH can efficiently reduce the interfacial charge transfer resistance and accelerate the photogenerated charge transfer. The free radical trapping test provided evidence for the essential role played by holes (h+) and superoxide radicals (·O2−) were involved in the degradation of RhB. The study provided a possibility to improve the photocatalytic efficiency of BiOCOOH.