Red photoluminescence due to energy transfer from Eu2+ to Cr3+ in BaAl12O19

Abstact: BaAl12O19-BaAl2O4 doped with Eu2+, Cr3+ and (Eu2++Cr3+) are prepared by solid-state reaction. The spectra of BaAl12O19-BaAl2O4:Eu2+, Cr3+ shows that the f-d emission bands from Eu2+ are centered at 442 and 495 nm and the Cr3+ yields the emission lines at 694 and 700 nm. Photoluminescence study demonstrates that the red photoluminescence and energy transfer occurs only in the phase of BaAl12O19 not BaAl2O4 though the samples are mixed phases. The fluorescence lifetime measurements indicate efficient energy transfer from Eu2+ to Cr3+ in BaAl12O19: Eu2+, Cr3+. The energy transfer rate and efficiency are calculated. The results show that the energy transfer rate and efficiency increase following the increase in Cr3+ concentration.