Speaker
Description
Blue-emitting phosphors hold significant potential for applications in solid-state lighting. We synthesised Y₂O₃ phosphors co-doped with 1 mol% Ce³⁺ and varying concentrations (1, 2, 3, and 4 mol%) of Eu²⁺ using the solution combustion method. Structural, compositional, optical absorption, and emission properties were investigated. X-ray diffraction analysis confirmed the formation of a cubic phase with the Ia-3 (206) space group, and the incorporation of dopants did not alter the host crystal structure. The Ce³⁺ doped sample exhibited a strong absorption band around 206 nm, which was observed to red-shift upon Eu²⁺ co-doping. Under 300 nm UV excitation, the Ce³⁺–Eu²⁺ co-doped samples displayed prominent blue emission, originating from the 5d → 4f transitions of Ce³⁺ (2F7/2, 2F5/2) and the allowed 4f⁶5d¹ → 4f⁷ transition of Eu²⁺. Photoluminescence spectra, excitation profiles, decay dynamics, and energy transfer efficiency analyses confirmed an efficient Ce³⁺ → Eu²⁺ energy transfer mechanism. The critical distance between Ce³⁺ and Eu²⁺ ions was calculated to be 4.56 Å, indicating exchange interaction as the dominant energy transfer pathway. These findings demonstrate that Y₂O₃:Ce³⁺, Eu²⁺ phosphors are promising candidates for use as blue light-emitting components in solid-state white lighting applications.
Keywords: Y2O3:Ce, Eu nanophosphor; Optical band gap; Photoluminescence; Energy transfer; Luminescence lifetime; Quenching
