Synthesis and photocatalytic activity of Na+ co-doped CaTiO3:Eu3+ photocatalysts for methylene blue degradation

Abstract The Na+ co-doped CaTiO3:Eu3+ powders were produced through the solution combustion method. The phase structure and optical properties of the synthesized samples were adequately characterized by X-ray diffraction (XRD), photoluminescence (PL) spectra, ultraviolet–visible (UV–vis) diffuse reflection spectroscopy and scanning electron microscopy (SEM). The XRD patterns revealed that a low level of Eu3+ doping could not cause lattice distortion of CaTiO3. Photoluminescence (PL) displayed the CaTiO3:0.5% Eu3+ sample synthesized at 900 °C has the weakest PL emission and the low electrons and holes recombination rate. The morphology of the sample was small nanoscale spherical particles. The UV–vis diffuse reflection spectra proved that doping Na+ and Eu3+ enlarged the absorption region and reduced band energy of pure CaTiO3. The photocatalytic properties of Na+ co-doped CaTiO3:Eu3+ samples were investigated via degrading methylene blue (MB) under ultraviolet light irradiation. The CaTiO3:0.5% Eu3+, 0.5% Na+ sample, by contrast, exhibited the greatest photocatalytic property and the degradation rate was as high as 96.62%, which makes it a promising multi-functional material (photocatalytic material and red phosphor) for decreasing organic pollution in water.