title: Triplet-Polaron-Interaction-Induced Upconversion from Triplet to Singlet: a Possible Way to Obtain Highly Efficient OLEDs.
abstract: Two D-A-type molecules, 4-N-[4-(9-phenylcarbazole)]-3,5-bis(4-diphenylamine)phenyl-4H-1,2,4-triazole and 4,4'-(9-(4-(1-phenyl-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-9H-carbazole-3,6-diyl) bis-(N,N-diphenylaniline), are designed and synthesized. Organic lightemitting diodes based on them exhibit deep-blue emission and the singlet formation ratios are higher than the simple spin-statistics of 25%. A triplet-polaroninteraction-induced upconversion from triplet to singlet through a one-electron transfer mechanism is proposed, and is proven by magnetocurrent measurement and quantum-chemistry computation.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China.
authors.forename: Ablikim
authors.initials: A
authors.lastname: Obolda
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China.
authors.forename: Qiming
authors.initials: Q
authors.lastname: Peng
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China.
authors.forename: Chuanyou
authors.initials: C
authors.lastname: He
authors.affiliation: Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China.
authors.forename: Tian
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China.
authors.forename: Jiajun
authors.initials: J
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Ma
authors.affiliation: Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Shuai
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
keywords: charge transfer; deep-blue emission; fluorescence; organic light-emitting devices; triplet-polaron interaction