Thermoluminescence and photoluminescence characteristics of nanocrystalline K₂Ca₂(SO₄)₃: Eu

Abstract

Nanocrystalline K2Ca2(SO4)3 : Eu prepared by a co-precipitation method has been studied for its thermoluminescence (TL) and photoluminescence (PL) characteristics. The TL glow curve of the compound has a simple structure with a prominent peak at 406 K and a small peak at 462 K. TL sensitivity of the phosphor is found to be more than that of TLD-100 (LiF) but quite less compared to TLD-700H (LiF : Mg, Cu, P). The presence of two overlapping bands at around 400 and 450 nm in the PL emission spectra of the phosphor (both unexposed and exposed to gamma radiation) suggests the presence of Eu2+ in the host compound occupying two different lattice sites. Moreover a reduction in TL sensitivity on decreasing the particle size (from 125 μm to 18.6 nm) gives a better understanding of the TL mechanism involved in the concerned phosphor. Fading and reusability of the phosphor are also studied and it is found that the phosphor is quite suitable for radiation dosimetry.