Novel Z-scheme visible-light-driven Ag3PO4/Ag/SiC photocatalysts with enhanced photocatalytic activity

Abstract

Visible-light-driven Ag₃PO₄/Ag/SiC photocatalysts with different weight fractions of SiC were synthesized via an in situ precipitation method and characterized by X-ray diffraction (XRD) and UV-vis diffuse reflectance spectroscopy (DRS). Under visible light irradiation (>420 nm), the Ag₃PO₄/Ag/SiC photocatalysts degraded methyl orange (MO) and phenol efficiently and displayed much higher photocatalytic activity than that of pure Ag₃PO₄/Ag or SiC/Ag, and the Ag₃PO₄/Ag/SiC hybrid photocatalyst with 10% of SiC exhibited the highest photocatalytic activity. The quenching effects of different scavengers demonstrated that reactive h⁺ and O₂˙⁻ played the major role in the MO degradation. It was elucidated that the excellent photocatalytic activity of Ag₃PO₄/Ag/SiC for the degradation of MO under visible light (λ > 420 nm) can be ascribed to the efficient separation of photogenerated electrons and holes through the Z-scheme system composed of Ag₃PO₄, Ag and SiC, in which the Ag nanoparticles acted as the charge transmission-bridge. The Ag₃PO₄/Ag/SiC hybrid maintained good photocatalytic activity after 10 times of cycle experiments.