Crystalline phase effect on the up-conversion processes and white emission of Yb/Er/Tm:YSiO nanocrystals.

Yb3+,Er3+,Tm3+:Y2Si2O7 nanopowders were fabricated by a sol-gel method and then annealed at two different temperatures of 1050 °C and 1480 °C for 12 h to investigate the phase effect on the structural and optical properties. X-ray diffraction patterns (XRD) of all powders revealed that most of the peaks were in good harmony with the standard JCPDS cards of Y2Si2O7 (PDF #38-0223 and PDF #38-0440). SEM images of the powders were taken to examine the morphology and chemical composition of the powders.