CdSiO_3:Eu~(3+) red nanophosphors prepared by low temperature solution combustion technique, its structural and luminescent properties

摘要

CdSiO_3:Eu~(3+) (0.5-5 mol%) nanophosphors were synthesized using oxalyl di-hydrazide fuel by solution combustion technique for the first time. The structural, thermo and photoluminescent properties were studied. The average particle size was estimated from transmission electron microscopy (TEM) studies and found to be in the range 20-30 nm. The values were in good agreement with Scherer's method and Williamson-Hall plots. Scanning electron microscope (SEM) showed highly porous, fluffy and many agglomerated particles. Photoluminescence (PL) CdSiO_3:Eu~(3+) (0.5-5 mol%) shows emission peaks at 577, 596,612,659 and 706 nm which were assigned to ~5D_0 -> ~7F_j (j = 0,1,2,3,4) transition respectively. It was observed that PL intensity increases up to the concentration 4 mol% Eu~(3+). Thermoluminescence (TL) studies were carried out on CdSiO_3:Eu~(3+) (1-5 mol%) nanophosphor by exposing to y-rays (1-6 kGy) and UV (5-25 min) respectively. The TL intensity was found to be highest in 1 mol% Eu~(3+) concentration. Further, effect of different gamma (1-6 kGy) and UV (5-25 min) exposure was studied on CdSiO_3:Eu~(3+) nanophosphor. Simple well resolved glow peak at ~178 °C was recorded for both the exposures. The TL intensity at 178 °C increase linearly with increase in the γ-dose. However, in UV exposed samples the TL glow peak intensity increase up to 10 min and thereafter the peak intensity decreases with further increase in exposure time. The effect of heating rate (β) and fading characteristics for y and UV were studied in CdSiO_3: Eu~(3+) (1 mol%). The kinetic parameters (E, b, s) were estimated using different theoretical methods.