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Published on: April 14, 2020
A highly-efficient blue-light excitable red phosphor: intramolecular π-stacking interactions in one dinuclear
Zhengliang Wang1, Hui Yang, Pei He
1Key Laboratory of Comprehensive Utilization of Mineral Resource in Ethnic Regions, Key Laboratory of Resource Clean Conversion in Ethnic Regions, Education Department of Yunnan, School of Chemistry & Environment, Yunnan Minzu University, Kunming, 650500, P. R. China. hee_csu@csu.edu.cn tanghuaijun@sohu.com.
Abstract:
A series of ternary dinuclear europium(iii) complexes [Eu2(2,7-BTFDBC)3-n(DBM)2n(Phen)2] (n = 0, 1, or 2) were synthesized by using 2,7-bis(4'4'4'-trifluoro-1,3-dioxobutyl)-(9-ethyl-9H-carbazole) (2,7-BTFDBC), dibenzoylmethane (DBM), 1,10-phenanthroline (Phen) and europium(iii) ions. All these complexes display a broad excitation band in the blue region and high intensity emission with high colour purity. The intensity of emission significantly increases with the increase of DBM in [Eu2(2,7-BTFDBC)3-n(DBM)2n(Phen)2] (n = 0, 1, or 2). The theoretical predictions of the molecular geometry and electronic absorption spectrum of [Eu2(2,7-BTFDBC)(DBM)4(Phen)2] confirm that the pendant phenyl domains engage in multiple T-shaped and parallel-displaced π-stacking interactions with the coordination sphere of two europium(iii) centers. Using [Eu2(2,7-BTFDBC)(DBM)4(Phen)2] as a red phosphor, a single red LED has been obtained with a ∼460 nm-emitting GaN chip.
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