Low temperature-synthesized MgAl2O4:Eu3+ nanophosphors and their structural validations using density functional theory: photoluminescence, photocatalytic, and electrochemical properties for multifunctional applications

A low temperature-assisted and oxalyl dihydrazide fuel-induced combustion synthesized series of uncalcined MgAl2O4:Eu3+ nanophosphors showed an average crystallite size of similar to 20 nm, and bandgap energy (E-g) of 4.50-5.15 eV, and were validated using density functional theory and found to match closely with the experimental values. The photoluminescence characteristic emission peaks of Eu3+ ions were recorded between 480 and 680 nm. The nanophosphors excited at 392 nm showed f-f transitions assigned as D-5(o)-F-7(J) (J = 0, 1, 2, and 3). The optimized MgAl2O4 phosphors had Commission Internationale de l'Eclairage coordinates in the red region, a correlated colour temperature of 2060 K, and a colour purity of 98.83%. The estimated luminescence quantum efficiency (eta) was observed to be similar to 63% using Judd-Ofelt analysis. Electrochemical and photocatalytic performance were explored and indicated its multifunctional applications. Therefore, MgAl2O4:Eu3+ nanophosphors could be used for the fabrication of light-emitting diodes, industrial dye degradation, and as electrodes for supercapacitor applications.