Photoluminescence properties and photocatalytic activities of SiO2@TiO2:Sm3+ nanomaterials

Dual functional Sm 3+ ion doped SiO 2 @TiO 2 composites were designed to investigate their luminescence properties and photocatalytic activities under ultraviolet and simulated solar light excitation, respectively. The TiO 2 :Sm 3+ nanoparticles , SiO 2 @TiO 2 :Sm 3+ nanospheres and SiO 2 @TiO 2 :Sm 3+ nanorods were successfully fabricated via the solvothermal method followed by the calcination at 700, 800 and 900 °C, respectively. The effects of morphology and calcination temperature on photocatalytic activities and luminescent properties were studied. The results demonstrated that the SiO 2 @TiO 2 :Sm 3+ nanorods calcined at 700 °C exhibited the highest luminescence intensities. This was attributed to possess the least specific surface area, which decreased the quenching center of surface defects , as well as without rutile phase. Moreover, SiO 2 @TiO 2 :Sm 3+ nanorods annealed at 800 °C were the optimum for improving the photodegradation efficiency of hydrolyzed polyacrylamide (HPAM) under simulated solar light irradiation. The degradation experiments results confirmed that the synergistic effect of the crystallinity/Ti–O–Si bond was the main reason for excellent photocatalytic activities. As a result, SiO 2 @TiO 2 :Sm 3+ nanorods meet our requirements for better photoluminescence intensities and photocatalytic activities.