Photoluminescence and Energy Transfer Study of Sr ₃ Y _0.96 (BO ₃ ) ₃ : _0.02 Ce ³⁺ _0.02 Mn ²⁺ Phosphor for WLED Application

Abstract

Abstract Sr 3 Y(BO 3 ) 3 ;Sr 3 Y 0.98 (BO 3 ) 3 : 0.02 Ce 3+ ;Sr 3 Y 0.98 (BO 3 ) 3 : 0.02 Mn 2+ Sr 3 Y 0.96 (BO 3 ): 0.02 Ce 3+ 0.02 Mn 2+ phosphors are synthesized by solution combustion method at 650 °C in muffle furnace. Synthesized phosphors are annealed at 950 °C for 3 h under weak reducing atmosphere provided by activated charcoal/carbon to achieve desire oxidation state of dopants. Photoluminescence study shows that Sr 3 Y 0.98 (BO 3 ) 3 : 0.02 Mn 2+ phosphors converts blue light (462 nm) into red (614 nm) due to 4 T 1(4G) to 6 A 1(6s) transition of Mn 2+ in host crystal. Sr 3 Y 0.98 (BO 3 ) 3 : 0.02 Ce 3+ converts UV radiation (261 nm: 2 f 5/2 → 5 d 1 of Ce 3+ ) into blue light of wavelength 486 nm which is attributed to the inter‐configuration 5 d 1 → 4 f 1 transition of Ce 3+ . In Sr 3 Y 0.96 (BO 3 ) 3 : 0.02 Ce 3+ 0.02 Mn 2+ phosphors resonant energy transfer occurs from Ce 3+ to Mn 2+ in host matrix, resulting into intense red emission (614 nm) from UV light (263 nm). Using photoluminescence intensity comparison, the study confirms the resonant‐ET from sensitizer Ce 3+ to activator Mn 2+ in the crystal. So the report it as UV‐activated red emitting phosphor for UV‐PC‐WLED.