Magnesium aluminate (MgAl2O4) nanophosphor doped with 10 wt% europium (Eu3+) was successfully synthesized via the sol-gel technique. X-ray diffraction analysis confirmed the formation of a single-phase cubic spinel structure, with an average crystallite size of 25 nm. Scanning electron microscopy revealed irregular, densely packed grains with rough surface morphology. Optical absorption studies showed broad absorption bands, indicating effective incorporation and interaction of Eu3+ ions within the MgAl2O4 host lattice. Upon excitation at 398 nm, the photoluminescence spectrum exhibited characteristic emissions corresponding to the 5D0 → 7FJ (J = 0–4) transitions of Eu3+ ions. A prominent red emission peak centred around 673 nm was observed, attributed to the 5D0 → 7F3 electric dipole transition, along with weaker emissions in the orange-red region from other transitions. The strong red emission intensity combined with good structural stability suggests that Eu3+-doped MgAl2O4 is a promising material for red-emitting phosphors in solid-state lighting and optoelectronic applications.
Jisha et al. (Mon,) studied this question.