Photoluminescence and photodegradation properties of SiO2@TiO2:Sm3+ with different coating effects

Bright orange-red emitting Sm3+ doped SiO2@TiO2 hybrid materials have been synthesized through solvothermal coating method. The effect of the ethanol/H2O solvent ratios on the morphology and microstructure has been investigated. And a systematic study of photo-degradation and photoluminescence performance of SiO2@TiO2:Sm3+ with different coating effect is performed. The luminescence intensity increased with the decrease in the amount of H2O due to the uniform dispersion of TiO2:Sm3+ on the SiO2 surface. However, the increase in the amount of H2O is beneficial to the improvement of the photo-degradation efficiency of methyl orange, the best efficiency reaches to 90.3% under 30 min simulated solar light irradiation. Moreover, the effect of Sm3+ doping concentration on particle size, emission intensity and photocatalysis has been discussed. The results manifested that the presence of Sm3+ ions not only endows the composite materials with luminescence properties but also enhances its photocatalytic activity, however, appropriate doping concentration is necessary.