Cu2(OH)PO4 microstructures were synthesized by the hydrothermal method using three different types cupric salts (Cu (NO3)2, CuSO4, Cu(CH3COO)2) as raw materials. The X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible-NIR absorption spectra were used to characterize the as-obtained products. The different anions (SO42-, CH3COO-, NO3-) have different shapes and polarities, which can generate different interactions in reaction bath, induced the difference of structure and morphology of the prepared Cu2(OH)PO4. The Cu2(OH)PO4 microstructures prepared form Cu(NO3)2•3H2O showed the best photocatalytic activity induced by near-infrared light to degrade 2,4-dichlorophenol (2,4-DCP) solution. Our work suggests that the active morphological surfaces as well as different coordination environments for the metal ions has an important influence on the photocatalytic performance of Cu2(OH)PO4 microstructure.

The composite Ag3PO4/CeO2 photocatlyst, a novel p-n type heterojunction, has been successfully fabricated through a facile hydrothermal process combined with a successive in situ precipitation technique. The X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and UV-visible diffuse reflectance spectra (DRS) were used to characterize the as-obtained products. The SEM and TEM image show that CeO2 particles have been successfully loaded and well distributed in the surface of Ag3PO4. The photocatalytic activities of the p-Ag3PO4/n-CeO2 heterojunctions were investigated for their efficiency on the degradation of Rhodamine B (RhB) under ultra-violet light and visible light irradiation, and the results showed that the p-Ag3PO4/n-CeO2 heterojunctions possessed remarkable photocatalytic activities. The enhanced photocatalytic activity can be attributed to the extended absorption in the visible light region resulting from the Ag3PO4 and the effective separation of photogenerated carriers driven by the internal electrostatic field in the junction region.

AbstractA highly efficient photocatalyst Ag3PO4/Ag was prepared by a one-step low temperature chemical bath method. The reflectance spectra (DRS) indicated Ag3PO4/Ag had strong absorption in visible light region. The synthesized Ag3PO4/Ag photocatalyst was used as the efficient photocatalysts for the photocatalytic degradation of Rhodamine B (RhB) under visible-light illumination which showed almost complete degradation (~ 98%) of RhB dye in 90 min. The negative surface of Ag3PO4/Ag photocatalyst also promoted the degradation of a cationic dye like methylene bule (MB; 78% in 90min), while the performance against an anionic dye like methyl orange was poorer (MO; 40% in 90 min). Compared to the pure Ag3PO4 photocatalyst, the Ag3PO4/Ag photocatalyst showed the enhanced visible light photocatalytic informance. The excellent photocatalytic performance is mainly ascribed to the surface plasmon resonance of Ag nanoparticles and a large negative charge of PO43- ions.