Highly efficient near-infrared emission in Er3+ doped silica films containing size-tunable SnO2 nanocrystals.

Co-doping size-tunable SnO2 nanocrystals into Er(3+) ions embedded silica thin films produces an enhancement of Er-related near-infrared emission by three orders of magnitude. Selective PL and PLE measurements show that energy transfer process occurs between SnO2 nanocrystals and Er(3+) ions. Quantitative studies of PL decay lifetime and photoluminescence temperature-dependence demonstrate that both high energy transfer efficiency from SnO2 nanocrystals to Er(3+) ions and the partial incorporation of Er(3+) ions into SnO2 nanocrystals contribute to the near-infrared emission enhancement. All these results indicated that SnO2 nanocrystals with suitable size have great potentials in fabricating high-efficiency near-infrared luminous materials as sensitizers of Er(3+) ions.