摘要
研究了Ｇａ３＋在ＳｒＳ∶Ｃｅ和ＳｒＧａ２Ｓ４∶Ｃｅ薄膜电致发光（ＴＦＥＬ）材料中的作用及其对Ｃｅ３＋发光特性的影响。在ＳｒＳ中掺入Ｇａ２Ｓ３并烧结，发现Ｇａ３＋的浓度增加时，Ｃｅ３＋的发光显著向短波方向移动，激发谱中对应于ＳｒＳ带间吸收的激发峰相对减弱，而对应于Ｃｅ３＋的基态到激发态跃迁的激发效率相对提高，并出现逐渐增强的ＳｒＧａ２Ｓ４的带间吸收。Ｇａ３＋的引入使Ｃｅ３＋周围的配位场发生变化，相应的能级分布有所改变，Ｓｒ２＋离子性的增强和Ｃｅ３＋－Ｃｅ３＋相互作用的减弱对Ｃｅ３＋发光特性有显著影响。
The electrooptical characteristics of SrS∶Ce and SrGa_2S_4∶Ce as two kinds of hopeful blue TFEL phosphor have been intensively investigated. The color purity of SrGa_2S_4∶Ce is better than that of SrS∶Ce. In this paper, the influence of Ga^3+ on PL characteristics is first reported. Ga_2S_3 was doped into SrS, then sintered. The emission spectra shift obviously towards short wavelength range with increase of Ga^3+ concentration. At the same time, the relative intensity of the excitation peaks corresponding to the interband absorption of SrS reduces, and the exciting efficiency corresponding to the transition from the ground states to the excited states of Ce^3+ ions increases. The ligand field around Ce^3+ is changed by doping Ga^3+. After occupied by Ce^3+ the ionicity of Sr^2+ becomes stronger and Ce^3+-Ce^3+ interaction becomes weaker. These factors are advantegeous for blue emission.
出处
《中国稀土学报》
CAS
CSCD
北大核心
1998年第2期121-125,共5页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金
