Ag3PO4 nanocrystals and g-C3N4 quantum dots decorated Ag2WO4 nanorods: ternary nanoheterostructures for photocatalytic degradation of organic contaminants in water†
Abstract
Visible-light-driven Ag3PO4/graphite-like carbon nitride/Ag2WO4 photocatalysts with different weight fractions of Ag3PO4 were synthesized. Ag2WO4 nanorods with a scale of 500 nm to 3 μm were prepared by using a hydrothermal reaction. Via a facile deposition–precipitation technique, graphite-like carbon nitride (g-C3N4) quantum dots and Ag3PO4 nanocrystals were then deposited onto the surface of Ag2WO4 nanorods sequentially. Under visible-light irradiation (λ > 420 nm), the Ag3PO4/g-C3N4/Ag2WO4 nanorods degraded Rh B efficiently and displayed much higher photocatalytic activity than that of pure Ag2WO4 and the g-C3N4/Ag2WO4 composite, and the Ag3PO4/g-C3N4/Ag2WO4 hybrid photocatalyst with 30 wt% of Ag3PO4 exhibited the highest photocatalytic activity. The quenching effects of different scavengers demonstrated that reactive h+ and ·O2− played the major roles in Rh B degradation. It was elucidated that the excellent photocatalytic activity of Ag3PO4/g-C3N4/Ag2WO4 for the degradation of Rh B under visible light (λ > 420 nm) can be ascribed to the efficient separation of photogenerated electrons and holes through the Ag3PO4/g-C3N4/Ag2WO4 heterostructure.