摘要
This study demonstrates the hydrothermal treatment of core-shell polytetrafluoroethylene (PTFE) nanoparticles decorated with TiO 2 (h-PTFE@TiO 2 ); this material exhibits strain-induced local dipole enhancement of the space-charge piezopotential that improves the photocatalytic effect. Under acoustic cavitation, dielectric barrier discharge and electric dipole formation are initiated in voids within the PTFE nanoparticles and at the TiO 2 –PTFE interface. The h-PTFE@TiO 2 nanoparticles (NPs) have exceptionally high catalytic activity in organic dye degradation because of the local dipole enhancement of photoinduced charge separation with a carrier lifetime of 3.14 ns. The observed rate constant of the h-PTFE@TiO 2 NPs in the piezophototronic reaction reaches 0.1388 min −1 , which is 17 times that of the photocatalytic reaction (0.0084 min −1 ) and 66 times that of the piezocatalytic reaction (0.0021 min −1 ). Computational simulation reveals that large strain-induced space charge piezoelectric polarization induces an internal electric field between the unsaturated PTFE (fluorine vacancies) and TiO 2 surface. The piezopotential has a critical role in band bending at PTFE-TiO 2 interfaces to enhance the electron-hole separation when PTFE is constrained in TiO 2 shells. Results of piezoresponse force microscopy reveal that the piezoelectric coefficient d 33 of PTFE is approximately 79.77 pCN −1 . The findings provide insights into catalytic activity for environmental remediation.