Synergy Between Oxygen Vacancies and Surface Plasmon Resonance Effect in of Bi@Vo-Bi2O3 for Efficient Photocatalytic Performance Under Visible Light

Abstract

It remains a significant challenge for a photocatalyst to achieve a broad light response, effective O₂ adsorption and long photogenerated carrier lifetime in the catalytic reaction. Herein, this study designs a plasmonic Bi@Vo-Bi₂O₃ core@shell heterojunction via the hydrothermal method and demonstrates the presence of surface oxygen vacancies identified with electron spin resonance. Importantly, O₂ temperature programmed desorption in combination with ultraviolet-visible diffuse reflectance spectra reveals the introduction of plasmonic Bi as the core of Bi@Vo-Bi₂O₃ effectively promotes O₂ adsorption by capturing electrons from the defect states and broad the light absorption response range, which synergistically promote catalytic activity on O₂ reduction to H₂O₂ production, pollutant degradation and antibacterial performance in pure water without sacrificial agent. Compared to the pure Bi₂O₃, the H₂O₂ yield of Bi@Vo-Bi₂O₃ is approximately two times greater than that of Bi₂O₃ under visible light. Additionally, the Schottky barrier interface in integrated Bi@Vo-Bi₂O₃ prevents the excited electrons from recombining with the holes. Furthermore, it was proven that ¹O₂ plays a prominent role in the degradation of Methylene blue, as confirmed by scavenger experiments and detailed experimental characterizations. This work's insights into the photocatalysis mechanism may guide the development of new photocatalysts for enhancing photocatalytic performance.