Bi2SiO5 nanosheets as piezo-photocatalyst for efficient degradation of 2,4-Dichlorophenol

Piezo-photocatalysis is an effective solution for degrading organic pollutants. In this study, BiSiO nanosheets are successfully synthesized via a one-step hydrothermal method. The piezo-photocatalytic degrading mechanisms of 2,4-Dichlorophenol (2,4-DCP) on BiSiO nanosheets are thoroughly investigated through the integration of experimental study and density functional theory (DFT) calculations. Experimental results revealed outstanding piezoelectric properties for BiSiO nanosheets with a piezoelectric coefficient of 250 pC/N, outperforming previously reported piezo-photocatalysts. The degradation rate constant of 2,4-DCP on BiSiO nanosheets reached 0.0891 min by piezo-photocatalysis, which is 17 and 1.8 times higher than that by solitary photo- and piezo-catalysis, respectively. Furthermore, DFT calculations for BiSiO explain the crucial role of piezoelectric effects in bending its band structure, regulating photogenerated carrier behaviors, and promoting reactive oxygen species (ROS) generation. Finally, the degradation pathways of 2,4-DCP on BiSiO nanosheets were revealed with details. The results of this study offer valuable insights for water treatment with piezo-photocatalysis.