Combustion synthesis and photoluminescence of Tb3+ doped LaAlO3 nanophosphors

Terbium doped lanthanum aluminate (LaAlO3) nanophosphors were successfully synthesized by a combustion process using concentrated solution of lanthanum nitrates and aluminate as oxidiser, and glycine acid as fuel. The powders were characterized by infrared spectroscopy (IR), X-ray diffraction (XRD), Rietveld refinement, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and fluorescence spectroscopy. Pure LaAlO3 phase was obtained at 800 °C heated for 4 h, without formation of any intermediate phase, with an average crystal size, as determined by TEM, of 60 nm. Intense green emission is reported at 542 nm, from the 5D45D4 level, which intensity depends on Tb concentration.

► LaAlO3:Tb3+ nanophosphors were successfully synthesized by a combustion process.
► Pure LaAlO3 phase was obtained at 800 °C (4 h), with an average crystal size of 60 nm.
► The most intense emission of Tb3+ in LaAlO3 was registered for the transition (5D4→7F55D4→7F5) at 542 nm.
► Up to 10% of Tb3+ doped LaAlO3, the luminescence intensity decreases because of concentration quenching.