Enhanced photocatalytic decomposition of methylene blue and toluene gas with hydrothermally coated TiO2-supported on Ag–CaAl2O4:Eu2+, Nd3+long-lasting phosphor

Titanium dioxide was coated by hydrothermal reaction on the surface of CaAl2O4:Eu2+,Nd3+long-lasting phosphor beads on which a silver noble metal was impregnated to enhance photocatalytic reactivity. The phosphor composite as a TiO2supporter was fabricated in the form of beads for convenient applications. Silver was impregnated on the CaAl2O4:Eu2+,Nd3+long-lasting phosphor using a silver nitrate aqueous solution prior to TiO2coating process. The morphological and compositional characteristics of the TiO2coated phosphor composite materials were measured using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray photoelectron spectrometer (XPS). The photocatalytic properties of the TiO2coated phosphor composite materials were analyzed through decompositions of both methylene blue dye solution and toluene gas under ultraviolet and visible light irradiation. Through measuring the variation of photocatalytic reaction with different Ag concentrations, 0.035 M Ag-impregnated TiO2/CaAl2O4:Eu2+,Nd3+phosphor composite showed the best photocatalysis efficiency under UV and visible light illumination.