Tunable Blue-Yellow Emission in LaInO3:Bi3+,Dy3+ Phosphors via Polyol Synthesis for Advanced LED Applications

The polyol synthesis method was employed to prepare LaInO3 perovskite phosphors doped with Bi3+ (x = 1, 3, 5 at.%) and co-doped with Dy3+ (y = 1-5 at.%). The X-ray diffraction (XRD) confirmed the formation of a pure orthorhombic LaInO3 phase in annealed samples. Morphological analysis revealed spherical agglomerates with some irregularities, ranging in size from 60 to 90 nm. The reduction of energy band gap on doping ions into lattice using DFT studies. The energy-dispersive spectroscopy (EDS) confirmed the successful incorporation of Bi3+ and Dy3+ ions into the LaInO3 lattice. The photoluminescence (PL) studies demonstrated that Bi3+-doped LaInO3 exhibited a broad blue emission peak at 432 nm due to the 3P1→1S0 transition of Bi3+ ions. On the other hand, LaInO3 doped with Dy3+ exhibited distinctive emissions at 482 nm (blue) and 584 nm (yellow), which correspond to the 4F9/2→6H15/2 and 4F9/2→6H13/2 transitions of Dy3+ ions, respectively. The optimized sample composition is found to be LaInO3: 3 at.% Bi3+, 3 at.% Dy3+ demonstrated enhanced emission intensities due to energy transfer from Bi3+ to Dy3+ ions making it a promising candidate for advanced LED applications.