Significant enhancement of piezoelectric photocatalytic activity in Mn-doped BiFeO3

Ultrasonic vibration and light irradiation can be used together to slow down the rapid recombination of light-induced charges during the catalytic process. One way to enhance the catalytic performance is by introducing different elements into the structure. In this study, pure bismuth ferrite (BiFeO3) and manganese (Mn)-doped bismuth ferrite (BFMO) nanomaterials were successfully synthesized by electrostatic spinning. These materials were then tested for their ability to degrade rhodamine B (RhB). The best-performing material was BiFe0.85Mn0.15O3, which achieved almost complete removal of RhB within 100 minutes. The degradation rate of this material was 3.3 times higher than that of pristine BiFeO3. This enhanced catalytic activity can be attributed to the wider range of light absorption and the synergistic enhancement of the piezoelectric response, which promotes the movement of free carriers. In addition, the synthesized catalysts have good stability and reusability, with little metal leaching after multiple uses. Free radical scavenging experiments tests showed that ·OH and holes are the main active species in the catalytic process. This work paves a new approach for creating highly efficient piezoelectric catalysts and expands the application of BiFeO3-based materials for wastewater purification.