Sonocatalytic evaluation of binary composites Bi12GeO20/GO in degradation of tetracycline hydrochloride

Abstract

A series of binary composites Bi12GeO20/GO were synthesized by incorporating graphene oxide (GO) during a facile chemical precipitation process of Bi12GeO20. Systematical analyses were conducted concerning the microstructure, morphology, and electrochemical and optical properties of these as-prepared composites. Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) confirmed the presence of both Bi12GeO20 and GO components, as well as the formation of heterostructures. Compared to bare Bi12GeO20, these composites demonstrated the enhanced sonocatalytic degradation efficiencies for tetracycline hydrochloride (TC). Additionally, the effects of reaction parameters, including catalyst dosage, initial concentration of TC, power, and frequency, on catalytic degradation were investigated. The best counterpart 3 % GB showed satisfactory adsorption and sonocatalytic degradation efficiency of approximately 48 % under the optimal conditions: catalyst concentration of 1.0 g/L, TC concentration of 5 mg/L, ultrasound power of 350 W, and frequency of 35 Hz. Based on the structure-effect relationship, the improved catalytic degradation efficiencies of these composites were primarily attributed to the incorporation of GO that effectively strengthened adsorption capability, boosted generation of reactive species, and suppressed the recombination of charge carriers. Eventually, the sonocatalysis mechanism was proposed according to entrapping experiments.