Study On Visible-light Photocatalytic Activity Of Ag₃PO₄/Cyclized Polyacrynitrile Composites

Ag3PO4 particles were prepared using Na2HPO4 and AgNO3 as raw materials. Then Ag3PO4/polyacrylonitrile (Ag3PO4/PAN) composites were obtained by chemical adsorption method. Finally, the Ag3PO4/polyacrylonitrile (Ag3PO4/PAN) composites were heat-treated to prepare Ag3PO4/cyclized polyacrylonitrile (Ag3PO4/CPAN) composites. The Ag3PO4/CPAN composites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflection spectroscopy (UV-Vis DRS) and photoluminescence spectroscopy (PL). SEM results show that both Ag3PO4 and Ag3PO4/CPAN composites display irregular spherical-like morphologies. XRD results show the crystal structure of Ag3PO4 particles modified by CPAN donot change. FT-IR and XPS show that CPAN attached to the surface of Ag3PO4. DRS results reveal that CPAN can increase the visible light absorption ability and PL shows that CPAN attached on the surface of Ag3PO4 reduces recombination possibility of the light induced electrons and holes. The photocatalytic activities of Ag3PO4/CPAN composites were evaluated by degradation of methyl orange aqueous solution. The effects of the preparation conditions such as mass ratio of CPAN and Ag3PO4, the calcination temperature on the photocatalytic activity of Ag3PO4/CPAN composites under visible light were discussed. The results show that the photocatalytic activity of the composites was much higher than that of Ag3PO4, and the optimum preparation condition is found that the mass ratio of Ag3PO4 and CPAN is 300:1, the calcination temperature is 180?, and the calcination time is 2.0 h. It is proposed that both h+ and ·O2- play an important role in the photocatalytic degradation of MO by Ag3PO4/CPAN composites under visible light.Ag3PO4/PAN composites were prepared by in situ growth of Ag3PO4 on CPAN surface with Na2HPO4 aqueous solution dropping into AgNO3 suspension (including PAN). Then Ag3PO4/CPAN composites were got by heat treatment. The crystal structure, morphology composition and optical absorption were studied by XRD, SEM, FT-IR and UV-Vis DRS. SEM results show that both Ag3PO4 and Ag3PO4/CPAN composites display irregular spherical-like morphologies. XRD results show the crystal structure of Ag3PO4 particles modified by CPAN donot change. FT-IR shows that PAN was transated into cyclized polyacrylonitrile. The photocatalytic activities of Ag3PO4/CPAN composites were studied by degradation of methyl orange aqueous solution. The results showed that Ag3PO4/CPAN composite particles have perfect photocatalytic activity when the content of CPAN is 4% and then thermal-treatment at 170? for 2h. The carriers scavenger experiment indicated that the photogenerated holes might be the main active species in MO photodegradation.