Piezocatalytic degradation of methylene blue, tetrabromobisphenol A and tetracycline hydrochloride using Bi4Ti3O12 with different morphologies

In this paper, we report the piezocatalytic application of morphologically different Bi4Ti3O12 nanostructures for piezocatalytic degradation of various environmental pollutants. Three types of Bi4Ti3O12 nanostructures with different morphologies, i.e. nanosheet-assembled hierarchical microrods, microplates, and nanoflake-assembled hierarchical microspheres, have been synthesized via a hydrothermal route and a molten salt route. Three typical environmental pollutants — methylene blue (MB), tetrabromobisphenol A (TBBPA) and tetracycline hydrochloride (TC) — were separately used the target pollutant to evaluate the piezocatalytic degradation performances of the as-synthesized Bi4Ti3O12 nanostructures under ultrasonic vibration. It is demonstrated that all the Bi4Ti3O12 samples exhibit a pronounced piezocatalytic degradation of these pollutants. The highest piezocatalytic degradation performance is observed for the Bi4Ti3O12 microplates. Further, the effects of pH, initial pollutant concentration, catalyst dosage and various anions on the piezocatalytic degradation of MB over the Bi4Ti3O12 microplates were investigated. A possible piezocatalytic mechanism of Bi4Ti3O12 was proposed and analyzed.