Unusual phosphorescence characteristics of Ir(ppy)3 in a solid matrix at low temperatures

被引：53

作者：

Goushi, K ^{[1
]}

Kawamura, Y ^{[1
]}

Sasabe, H ^{[1
]}

Adachi, C ^{[1
]}

机构：

[1] CIST, Dept Photon Mat Sci, Chitose, Hokkaido 0668655, Japan

来源：

JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS | 2004年 / 43卷 / 7A期

基金：

中国国家自然科学基金;

关键词：

phosphorescence; Ir(ppy)(3); OLED; electroluminescence; MLCT; triplet; lifetime;

D O I：

10.1143/JJAP.43.L937

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We observed unusual radiative decay characteristics of a (fac-tris(2-phenylpyridine)iridium [Ir(ppy)(3)]) triplet-excited state doped into 4,4'-N,N-dicarbazole-biphenyl (CBP) and polymethylmethacrylate (PMMA) host matrices. Front a measurement of the temperature dependence on the phosphorescence intensity and the lifetime of Ir(ppy)(3) in these hosts, we observed that phosphorescence intensities are independent of temperature, while the lifetimes significantly increase at temperatures below T similar to 50 K. These results lead us to conclude that the non-radiative transition rate (k(nr)) from the triplet excited state is very small compared with the radiative transition rate (k(r)) and that the phosphorescence quantum yield (phi(PH)) is nearly 100% even at room temperature. Based on Our experimental results, we propose a possible decay mechanism to rationalize the characteristic temperature dependence on the transient phosphorescence.

引用

页码：L937 / L939

页数：3

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