Bond energy, preferential occupancy and spontaneous reduction ability of Eu3+ doped in CaAl2Si2O8

被引：38

作者：

Li, Ling ^{[1
]}

Pan, Yu ^{[1
]}

Wang, Wenjun ^{[1
]}

Zhu, Yuhan ^{[1
]}

Zhang, Wenying ^{[1
]}

Xu, Haibing ^{[1
]}

Zhou, Liqun ^{[1
]}

Liu, Xiaoguang ^{[1
]}

机构：

[1] Hubei Univ, Hubei Collaborat Innovat Ctr Adv Organochem Mat, Minist Educ, Key Lab Synth & Applicat Organ Funct Mol, Wuhan 430062, Hubei, Peoples R China

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2018年 / 731卷

关键词：

Bond energy; Site occupancy; Co-existence of Eu3+ and Eu2+; Chemical bond viewpoint; Bond valence model; CaAl2Si2O8:Eu; LUMINESCENCE PROPERTIES; WHITE-LIGHT; CRYSTAL-STRUCTURE; RECENT PROGRESS; RED EMISSION; EU2+; PHOSPHORS; AIR; REFINEMENT;

D O I：

10.1016/j.jallcom.2017.10.054

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A bond-energy method is used to determine the site occupancy preference of Eu3+ or Eu2+ and further firstly extended to study the spontaneous reduction of Eu3+ doped CaAl2Si2O8 based on the bond valence model. The phosphor CaAl2Si2O8: Eu was synthesized under air condition. The co-existence of Eu3+ and Eu2+ cations was detected through photoluminescence measurement. The occupancy of Eu3+ or Eu2+ in CaAl2Si2O8 can be determined by comparing the deviation of its bond energy in different locations at Ca2+, Si4+ and Al3+ sites. Theoretical calculation result indicates that the Eu3+ and Eu2+ would preferentially occupy the smaller energy variation sites Ca4, which can be assigned to Eu4 site. The more important result is that the energy variation of Eu2+ at Eu4 sites is smaller than that of Eu3+ at the same sites, which indicates that Eu2+ is more stable than Eu3+ at Eu4 sites, so the spontaneous Eu3+-> Eu2+ reduction can be found in the CaAl2Si2O8. The same bond energy method can be extended to explain the reason why the Sm3+ doped CaAl2Si2O8 can't be reduced into Sm2+ under reduction condition. The theoretical result is consistent with the experimental phenomenon. This should help us to have a further understanding of spontaneous Eu3+-> Eu2+ reduction in the inorganic material. (C) 2017 Elsevier B.V. All rights reserved.

引用

页码：496 / 503

页数：8