Synthesis, characterisation and luminescence investigations of Eu activated CaAl2O4 phosphor

Europium ion doped monoclinic CaAl2O4 phosphors were obtained at low temperatures (500 °C) by the combustion of corresponding metal nitrate–urea mixtures, over a time of 5 min. The product was investigated by X-ray powder diffraction, TEM and SEM. Photoluminescence spectra revealed that europium ions were present in divalent oxidation states. Electron paramagnetic resonance (EPR) measurements at X-band showed the presence of fine structure transitions from Eu2+ ions in CaAl2O4:Eu.