Synthesis of novel Cd2P2O7/Ag3PO4 photocatalyst with enhanced visible-light photocatalytic performance and the enhancement mechanism

Abstract Novel Cd 2 P 2 O 7 /Ag 3 PO 4 photocatalysts containing different mass fractions of Cd 2 P 2 O 7 were synthesized by a hydrothermal method. The photocatalysts were characterized by X-ray diffractometry, transmission electron microscopy, X-ray photoelectron spectroscopy, Electron spin resonance (ESR), Fourier transform infrared spectrometry, ultraviolet–visible absorption spectroscopy and photoluminescence spectroscopy. Photocatalytic activity was decided by the effective separation and low recombination rate of photogenerated electron-hole pairs. During the experiments, the Cd 2 P 2 O 7 /Ag 3 PO 4 composites possessed fierce electron- hole separation capacity. In particular, the 1 wt% Cd 2 P 2 O 7 /Ag 3 PO 4 catalyst displayed higher photocatalytic performance than pure Ag 3 PO 4 under visible-light irradiation (λ>420 nm). The ESR spectrum showed the main active species during the methyl orange degradation were ·OH and ·O 2 − .