Journal of Inorganic Materials ›› 2016, Vol. 31 ›› Issue (8): 819-826.doi: 10.15541/jim20150624

• Orginal Article • Previous Articles     Next Articles

Influence of Eu2+ and Dy3+ Concentrations on Fluorescence and Phosphorescence of Sr2MgSi2O7 Phosphors

Qi-Nan MAO(), He LI, Zhen-Guo JI(), Jun-Hua XI, Jun ZHANG, Zhe KONG   

  1. College of Materials &Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
  • Received:2015-12-14 Revised:2016-01-20 Online:2016-08-20 Published:2016-07-20
  • About author:MAO Qi-Nan. E-mail: maoqinan@hdu.edu.cn
  • Supported by:
    National Natural Science Foundation of China (61372025);Zhejiang Provincial Natural Science Foundation of China (LY15E030009);Science and Technology Project of Zhejiang Province (2014C33220, 2015C37037)

Abstract:

Eu2+-doped Sr2MgSi2O7 and Eu2+ and Dy3+ codoped Sr2MgSi2O7 phosphors were synthesized by conventional solid-state reaction. Eu2+ and Dy3+ concentration effects on the fluorescence and phosphorescence of Sr2MgSi2O7 phosphors were studied. All the samples show a broad emission band centered at about 470 nm, which are ascribed to 4f65d→4f7 transition of Eu2+ ions. Concentration quenching is found to be the dominant factor decreasing emission intensity and afterglow duration time when Eu2+ doping level exceeds the critical concentration. Redshift of the emission bands is also observed as the Eu2+ concentration increasing. In order to explain the redshift of the emission bands, the centroid position of 5d level of Eu2+, crystal-field splitting energy and Stokes shift are estimated from excitation and emission spectra. Based on the calculation, the redshift of the emission bands mainly results from the variations of crystal-field splitting energy and Stokes shift, but is less influenced by the nephelauxetic effect. The Dy3+ ions suppress the fluorescence but enhance the phosphorescence lifetime. When the Dy3+ concentration is over 10mol%, the phosphorescence lifetime is shortened, because of concentration quenching of the Eu2+\Dy3+ ions by the mechanism of tunneling recombination.

Key words: Sr2MgSi2O7, luminescent property, doping, concentration quenching

CLC Number: 

  • TB34