Europium luminescence enhancement in Al2O3:Eu3+ powders prepared by direct combustion synthesis

The luminescence properties of Eu3+:Al2O3 powders prepared via low temperature direct combustion synthesis was investigated. It was observed that the heat treatment of the powders modifies the dynamics of the radiative transition D05→F27 of Eu3+ (1.0mol%) and produces an enhancement of the luminescence intensity by nearly one order of magnitude. The luminescence enhancement is attributed to the presence of Eu3+ in α-Al2O3 crystalline phase as the heat treatment drastically reduces the amount of amorphous Al2O3 phases present in the powder.