Enhanced blue emission and energy transfer in Ce 3+ /Eu 2+ Co-doped Sr 3 Y(PO 4 ) 3 phosphors synthesized via sol–gel method

Ce3+ and Eu2+ co-doped Sr3Y(PO4)3 phosphors were synthesized using the sol–gel method and systematically characterized to evaluate their structural and optical performance. X-ray diffraction confirmed the formation of a single-phase hexagonal Sr3Y(PO4)3 host with no detectable impurity phases, and the average crystallite size was estimated to be ∼23 nm using the Scherrer equation. Rietveld refinement exhibited satisfactory agreement between the observed and calculated diffraction profiles, with Rwp = 13.42 and χ2 = 1.42. FTIR analysis confirmed the characteristic vibrational modes of PO4³- groups, while SEM-EDS verified the presence of Sr, Y, P, O, Ce, and Eu in the prepared phosphor. Photoluminescence analysis revealed strong near-UV absorption and broad blue emission for both dopants, with a remarkable enhancement in Eu2+ emission due to efficient Ce3+→Eu2+ energy transfer. Concentration-dependent studies indicated quenching at higher dopant levels, governed by multipolar and exchange interactions. CIE analysis demonstrated blue to violetish-blue emission with a maximum color purity of 98.49%, demonstrating the suitability of this phosphor for blue LEDs and solid-state lighting. With stable luminescence behavior and promising optical properties, the prepared materials also show potential for horticultural illumination applications requiring controlled blue spectral output.