Piezotronics-enhanced photocatalytic performance of hierarchical dandelion-like Bi4Ti3O12/BaTiO3 for dye degradation

Photocatalysis exhibits superior catalytic performance, but its application in wastewater treatment faces challenges of water quality impact, limited removal efficiency, and instability. Piezo-catalysis, as a green and low-carbon catalytic technology, has great potential for wastewater treatment. In this study, we prepared a dandelion-like Bi 4 Ti 3 O 12 /BaTiO 3 catalyst via a template-free and one-step solvothermal method. The hierarchical microstructure assembled from nanosheets and nanoparticles was formed due to the shear effect of potassium hydroxide (KOH) and directional adsorption during the reaction process, and it has a high specific surface area and outstanding piezo-photocatalytic performance compared to individual Bi 4 Ti 3 O 12 or BaTiO 3 catalysts. The piezo-photocatalytic degradation efficiency of dyes by Bi 4 Ti 3 O 12 /BaTiO 3 reaches 99.5 %, and demonstrates excellent stability and wide applicability. This result was ascribed to the synergistic effect of heterojunction band structure and piezoelectric properties. Furthermore, the removal mechanism analysis indicates that the holes (h + ) and superoxide radical (O 2 − ) play a major role in the piezo-photocatalytic degradation of dyes. This work presents a novel method for developing efficient piezo-photocatalytic composite catalysts with a broad prospect for wastewater treatment.