Probe of Color Tunable Luminescence Attributes of YAlO₃ Nanophosphor Through Co-doping of Eu³⁺ and Tb³⁺ Ions

The facile and economical urea supported solution combustion synthesis approach was used to synthesize a series of Eu³⁺/Tb³⁺ co-doped YAlO₃ nano-regime luminous materials. The obtained phosphor samples were scrupulously assessed using an array of structural and spectroscopic studies. The X-ray diffraction and the Rietveld refinement technique were used to elucidate the single phase crystal structure of synthesized Y_1−x−yEu_xTb_yAlO₃ co-doped phosphors. The synthesized nanophosphors were crystallized in orthorhombic crystal system having space group Pbnm (62). Surface morphological investigations i.e. field emission scanning electron microscopy, and transmission electron microscope validated spherical shaped particles with clear boundaries in nano-range. The integration of Eu³⁺ and Tb³⁺ ions into YAlO₃ host matrix was assessed by using energy dispersive X-ray analysis of Y_0.94Eu_0.05Tb_0.01AlO₃ phosphor. The optical band gap values of Y_0.99Eu_0.01AlO₃, Y_0.99Tb_0.01AlO₃, and Y_0.99Eu_xTb_0.01AlO₃ (x = 0.01, 0.03, 0.05, 0.07 mol) nanocrystalline phosphor were assessed using diffuse reflectance spectroscopy observations. The meticulous investigation of the photoluminescence excitation and photoluminescence emission spectra of Y_1−x−0.01Eu_xTb_0.01AlO₃ (x = 0.01, 0.03, 0.05, 0.07 mol) revealed that Tb³⁺ efficiently sensitized Eu³⁺ ion and energy transfer can be effectively controlled by carefully fine-tuning the concentration of Eu³⁺ to accomplish color-tunable emission. The concentration quenching i.e. non-radiant energy loss phenomenon was appeared at x = 0.05 mol (Eu³⁺) in Y_1−x−0.01Eu_xTb_0.01AlO₃ nanophosphors. It emerged that the non-radiant energy loss phenomenon observed in focused co-doped phosphors had been caused by the quadrupole–quadrupole interaction. Commission International de I'Eclairage 1931 constraints, including the color coordinates (x, y), color purity, and color correlated temperature, were derived from the photoluminescence emission data for Y_1−x−0.01Eu_xTb_0.01AlO₃ (x = 0.01, 0.03, 0.05, 0.07 mol) luminescent materials. The Commission International de I'Eclairage 1931 color coordinates suggested that the hue could have been vigilant i.e., from yellow orange to crimson color region in Y_0.99−xEu_xTb_0.01AlO₃ nanosamples with divergences in the Eu³⁺ ion concentration. Our study sheds significant information on the possible myriad interactions amid these dopants revealing the important ways causing the observed photoluminescence spikes. This study work contributes to the understanding of the co-doping effects of rare earth ions and opens up new design possibilities for improved luminous materials that can be used in advanced optoelectronic solid-state lighting systems, lasers, light emitting diodes, and display systems.