Luminescence characteristics of Na21(SO4)7F6Cl:Cu+ phosphor

Abstract

ABSTRACTCopper-doped Na21(SO4)7F6Cl phosphor was synthesized via the conventional wet chemical method. The synthesis was carried using CuCl2 and Cu (NO3)2·3H2O as dopants in two different steps successively. The formation and phase purity of the compound were revealed by the X-ray diffraction pattern. Functional groups of the prepared phosphor were observed in the FT–IR spectrum. The emission along with excitation spectra were followed to explore the luminescence attributes. Photoluminescence (PL) emission spectrum of the material synthesized using CuCl2 as the dopant was observed at 358 nm due to 3dl0↔3d94s transitions when excited around 247 nm for various copper concentrations. Efficient blue emissions were obtained at peaks 423 and 469 nm for materials synthesized using Cu (NO3)2·3H2O as the dopant, when monitored at 357 nm excitation. The Commission Internationale de I’Eclairage chromaticity coordinates for different copper concentrations were calculated for the emission around 423 nm. TL glow curves of Na21(SO4)7F6Cl:Cu phosphor for different dopant concentrations, irradiated with 100 Gy gamma dose, were studied and hence the trap parameters, namely order of kinetics (b), activation energy (E) and frequency factor (s) associated with the most intensive glow peak of Na21(SO4)7F6Cl:Cu phosphor were determined by using Chen’s Peak shape method. The results indicate that Na21(SO4)7F6Cl:Cu+ is a potential novel blue-emitting lamp phosphor and may be quite suitable for use in dosimetry of ionizing radiations.