Piezotronics boosted plasmonic localization and hot electron injection of coralline-like Ag/BaTiO3 nanoarrays for photocatalytic application

Abstract

Metal-semiconductor piezo-photocatalysts are generally investigated due to their high photocatalytic performances by the coupling effect of piezotronics and localized surface plasmon resonance (LSPR). However, the mechanism is still indistinct, even the charge migration route is disputable. Here, the electron migration from Ag to BaTiO₃ has been confirmed by electron spin resonance (ESR) and radical trapping experiments. Furthermore, this work first proposes that piezoelectric field can promote the photocatalytic properties through electrical modulation of plasmon-exciton interaction. To exactly reveal the mechanism, the piezo-photocatalysis process is fully simulated by numerical analysis and finite element method (FEM). The unabridged mechanism of piezotronics boosted photocatalysis of LSPR-BaTiO₃ shows that piezoelectric field can modulate LSPR to generate more hot electrons, suppress Schottky barrier for improved hot electron injection from Ag to BaTiO₃ and restrain the recombination of electron–hole pairs by spatial separation of opposite charges.