Luminescence and thermoluminescence properties of a red emitting phosphor, Sr4Al14O25:Eu3+

Abstract

Sr4−xAl14O25:xEu3+ (x varies from 0.02 to 0.06) phosphors were prepared at high temperature via solid-state method. The crystal structure of Sr4Al14O25:Eu3+ was determined to be orthorhombic crystal system with Pmmm space group. The excitation spectrum of Sr3.96Al14O25:0.04Eu3+ shows four excitation bands at 308 nm, 360 nm, 383 nm, and 411 nm, respectively. The first excitation band, which is centered at 308 nm, is assigned to the charge-transfer (CTLM) band of Eu3+-O2−, and others are assigned to intra-4f transitions between 393 nm and 450 nm. The emission spectrum of Sr3.96Al14O25:0.04Eu3+ exhibits a series of emission bands which are attributed to the 5D0-7Fj (j = 0–4) transitions of Eu3+ ions. The luminescence studies revealed that the Eu3+ ions show high luminescence efficiency in emitting red light at 616 nm. The thermo-luminescence glow curve of Sr3.96Al14O25:0.04Eu3+ shows three overlapped glow peaks between 100 °C and 400 °C which are related to the defects at different trap depths. One of the selected glow curves was analyzed by using glow curve deconvolution (GCD) method. In order to explore the related kinetic parameters of P1 Gartia, Singh & Mazumdar peak shape (PS) method was also used.