Piezoelectric shield Schottky barrier coupling LSPR effect promoted the elimination of 2,4-dichlorophenol by Bi@Bi2WO6

The piezoelectric polarization significantly influences the behavior of charge carrier transfer. In this study, we successfully synthesized a Bi@Bi2WO6 Schottky heterojunction, employing a solvothermal method that incorporates a coupling mechanism integrating localized surface plasmon resonance (LSPR) and the piezoelectric effect. Upon exposure to both illumination and ultrasonic treatment, Bi@Bi2WO6 demonstrated optimal piezo-photocatalytic performance, achieving a remarkable 94.3 % degradation rate of 2,4-dichlorophenol (2,4-DCP) within 90 min. This removal efficiency was 3.0 times higher than that of metallic Bi and 2.1 times higher than pure Bi2WO6. The observed reduction in the band gap of Bi@Bi2WO6 (2.94–2.18 eV) can be attributed to resonant light absorption induced by local near-field enhancement, known as the LSPR effect. The notable piezoelectric response of Bi@Bi2WO6 exacerbated the compression of the Schottky barrier height (SBH). The photocurrent-time curve (I-T) showed a significant difference, indicating a reduced SBH at the space charge region, thereby enhancing the transfer of charge carriers at the interface. This led to a strong directional injection efficiency of hot electrons, accounting for the observed discrepancies in catalytic performance. A logical extension of this research was to investigate the immediate impact of the plasma-catalyst, characterized by a highly sensitive piezoelectric response, on photon transformation.