Afterglow performance enhancement and mechanism studies on Y2O2S:Eu,Mg,Ti prepared via cold isostatic pressing

作者：Zhou, Xiaolin; Xing, Mingming^*; Jiang, Tao; Fu, Yao; Peng, Yong; Wang, Hong; Luo, Xixian

来源：Journal of Alloys and Compounds, 2014, 585: 376-383.

DOI：10.1016/j.jallcom.2013.09.155

• Red long afterglow
• Y2O2S:Eu,Mg,Ti
• Cold isostatic pressing

A Y2O2S:Eu,Mg,Ti material was prepared via a modified sulphide-fusion route. Compared with the traditional solid-state reaction method, the obtained Y2O2S:Eu,Mg,Ti showed smaller, more uniform particles with higher brightness. The afterglow mechanism study indicated that the long-afterglow material is process-dependent and that its performance is determined by recipe, preparation technology and process used. The luminescence centres of Y2O2S:Ti; Y2O2S: Eu, Ti and Y2O2S:Eu,Mg,Ti are Ti4+ ions, Ti4+ + Eu3+ ions and Ti4+ + Eu3+ ions, respectively. The afterglow decay curve cannot be fitted using the exponential equation or first-, second-, third-order exponential decay multiple equations beyond 30 min. The afterglow luminescence of the materials resulted from Ti-related defects that make up two new trap levels. Ti doping created numerous harmful companying defects that decrease luminescence efficiency. Doping of Mg2+ ions facilitated the introduction of Ti4+ ions into the Y2O2S lattice to effectively modulate the depth and concentration of the trap. Doping of Mg2+-Ti4+ ion pairs reduced the number of harmful defects through the formation of a compensation-type hetero-valent substitution solid solution that greatly enhance the afterglow performance. Cold isostatic pressing promoted the entry of Ti ions into the Y2O2S crystal lattice and eliminated defects, such as preferred orientation. In addition, cold isostatic pressing reduced the E-2 to 0.9 eV, which is beneficial to the long afterglow of the resulting material at room temperature.

• 出版日期2014-2-5
• 单位大连海事大学