Effect of pulverising process on the luminescence properties of Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺

School of Materials Science and Engineering, Wuhan University of Technology, 430070 Wuhan, P.R. China

^a e-mail: whutho@163.com

Received: 12 April 2015
Revised: 7 June 2015
Accepted: 27 July 2015
Published online: 25 August 2015

Abstract

Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺ was selected to study the effect of pulverising process on the luminescence properties. The samples were characterised by X-ray diffraction (XRD), photoluminescence (PL), decay curves, thermoluminescence spectra (TL), scanning electron microscopy (SEM) and energy dispersive spectrometers (EDS). Results show that the pulverising process has no obvious effect on the position of the peak in the excitation and emission spectra, and the long afterglow performance of Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺ phosphor is impaired gradually with the increase of specific surface area. When the specific surface area is below 3500 cm²/g, both the decay constant of the afterglow and the depth of trap increase simultaneously. Once the specific surface area is more than 3500 cm²/g, however, both of them remain almost constant. Further, the decrease of the density of traps shows a linear relationship with the specific surface area. In addition, the agglomeration of Dy³⁺ is clearly observed in the Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺ samples after smashing, and the element O tends to exist in the grain rather than on the grain surface.