Synergistic effect of piezoelectricity and LSPR effect to boost efficient photocatalytic CO ₂ RR

Abstract The application of a piezoelectric field based on photocatalytic CO 2 reduction reaction is a new strategy to overcome the rapid charge recombination. Herein, NaNbO 3 –Ag–AgBr heterojunction synergizing piezoelectric polarization and the localized surface plasmon resonance (LSPR) effect is designed. Under the simultaneous excitation of light and ultrasound, piezoelectric field drives the separation of directional charge, and Ag nanoparticles enhance the absorption of visible light and the injection of hot electrons. Meanwhile, the mechanism of carrier transport in heterojunction under the synergistic action of piezoelectric field and LSPR effect is also studied. The research shows the CO yield of NaNbO 3 ‐Ag‐AgBr is 153.21 µmol g −1 and nearly 17 times higher than that of NaNbO 3 . In situ infrared spectroscopy, piezoresponse force microscopy (PFM) and Kelvin probe force microscopy (KPFM) results show that piezoelectric polarization reduces the Schottky barrier at the interface, promotes the transfer of hot electrons and inhibits the rapid bulk phase charge recombination. Thus, the piezoelectric photocatalytic system provides more profound insights for photocatalytic CO 2 RR.