Different luminescence behaviors of SnO₂/Eu³⁺ and SnO₂/Tm³⁺ co-doped phosphate glasses

In this Letter, the 75P₂O₅-25SrO phosphate glass co-doped with SnO₂/Tm³⁺ and SnO₂/Eu³⁺ were prepared and their photoluminescence spectra were investigated. Compared with the singly SnO₂, Tm³⁺ ions or Eu³⁺ ions doped glasses, the SnO₂/Tm³⁺ co-doped sample exhibit an enhanced Tm³⁺ ions emissions at 455 and 698 nm and the constant SnO₂ emission, while for the SnO₂/Eu³⁺ co-doped sample, all emissions of Eu³⁺ ions increased at the cost of SnO₂ emission. The different luminescence behaviors of these glasses were discussed and an energy transfer mechanism from SnO₂ to Tm³⁺ ions was proposed combined the down-conversion and the sub-up-conversion processes.