Pr3+1S0→Cr3+ energy transfer and ESR investigation in Pr3+ and Cr3+ activated SrAl12O19 quantum cutting phosphor

With the help of the Dexter's theory, the energy transfer mechanism from Pr3+1S0 to Cr3+ is investigated theoretically in SrAl12O19:Pr3+, Cr3+ quantum cutting phosphors. The electron spin resonance (ESR) spectra of Pr3+ and Cr3+-doped SrAl12O19 with magnetoplumbite structure have been studied. The Cr3+ ion is found to enter the Al4(4f) site, which is very close to the Sr(2d) site replaced by the Pr3+ ions in the host. The theoretical results indicate that the efficient Pr3+1S0→Cr3+ energy transfer can only take place in the intermediate mirror planes, in which for the nearest and next-nearest Pr3+-Cr3+ pairs, both dipole-dipole and dipole-quadrupole interactions can play their parts in the transfer. Finally, an overview is given about the research on the energy transfer from Pr3+1S0 to codopants in their co-doped materials.