Energy transfer and enhanced 1532 nm emission in Er3+ and Ce3+ co-doped Y3Al5O12 nano-particles

A series of Y3Al5O12:Ce3+, Er3+ (YAG:Ce, Er) nano-particles were synthesized by polymer-assisted sol–gel method. X-ray diffraction measurements reveal that a pure crystalline phase of YAG is achieved at temperature as low as 800 °C. The energy transfer from Ce3+ to Er3+ is studied based on photoluminescence spectroscopy and fluorescence decay patterns. It results that the emission intensity of Er3+ at near infrared (NIR) 1532 nm under indirect excitation of Ce3+ (460 nm) is 10 times stronger than that of direct excitation of Er3+ (275 or 380 nm). The energy transfer efficiency is estimated as 95.5% for YAG:Ce0.03Er0.09 sample. The very efficient energy transfer path and mechanism are also discussed.

► Pure garnet crystal phase was obtained at annealing temperature as low as 800 °C. ► The near infrared 1532 nm emission of Er3+ is 10 times enhanced. ► The enhancement is due to the energy transfer from Ce3+ to Er3+ ions. ► The near infrared emission is further enhanced by the cross-relaxation process.