Hydroxyapatite supported Ag3PO4 nanoparticles with higher visible light photocatalytic activity

Abstract Hydroxyapatite supported Ag 3 PO 4 nanocomposites have been synthesized by a wet impregnation process. UV–vis absorption spectra show a red shift of the absorption edges for the composite systems compared to pure hydroxyapatite support. The surface structure and morphology of the nanocomposites were characterized by Brunauer–Emmett–Teller (BET) apparatus, X-ray diffraction (XRD), transmission electron microscopy (TEM). The results suggest that Ag 3 PO 4 nanoparticles (6–17 nm in diameter) are well dispersed on the hydroxyapatite support and Ag 3 PO 4 nanoparticles density is larger for the higher Ag + loading sample. The as-prepared nanocomposite photocatalysts showed a pronounced photocatalytic activity upon decomposition of methylene blue dye in aqueous solution under both visible light (wavelength > 400 nm) and UV–vis light irradiation. A synergic mechanism of inherent photocatalytic capability of Ag 3 PO 4 and the accelerated electron/hole separation resulting from the photoinduced electrons captured by the slow-released Ag + at the interface of Ag 3 PO 4 and hydroxyapatite is proposed for the nanocomposites on the enhancement of photocatalytic performance in comparison to that of pure Ag 3 PO 4 nanoparticles. The support of hydroxyapatite may also act as an absorbent which favors the mass transfer in heterogeneous photocatalysis reaction.