Ultrasound assisted sonochemical synthesis of samarium doped Y_2O_3 nanostructures for display applications

摘要

Sm~(3+) doped (1-11 mol %) cubic Y_2O_3 nanoflowers were fabricated by simple low temperature Sonochemical method using Aloe Vera gel as fuel. The product was characterized by PXRD, SEM, TEM, DRS, PL etc. The powder X-ray diffraction (PXRD) profiles of nanophosphors showed cubic phase structure. The particle size was further confirmed by transmission electron microscope (TEM) and it was found to be in the range of 17-25 nm. The PL emission results reveal that the phosphor nanoparticles (NPs) emit an intensive yellowish light under 367 nm excitation. The excitation spectrum of Y_2O_3 : Sm~(3+) (5 mol %) obtained by monitoring the emission of the 4f - 4f (~4G_(5/2)→~6H_(7/2)) transition of Sm~(3+) at 612 nm As can be seen that the excitation spectrum consists of strong band at 332 nm and a broad band centered at 367 nm which corresponds to host absorption, confirming the effective energy transfer from Y_2O_3 host to Sm~(3+) ions. In the present study, CIE and CCT were estimated and found to be (0.45688, 0.51727) and the CCT of Y_2O_3: Sm~(3+) at 367 nm excitation was found to be 3357 K which was within the range of vertical daylight. Thus it can be useful for artificial production of illumination devices.