The Triplet State Conversion to Singlet Excited State in OLED

doi:10.7517/j.issn.1674-0475.2014.03.217

Abstract

Abstract:

The interesting in the field of OLED study is how make the most of the application of triplet exciton for enhancing the efficiency of electro-luminescent conversion in device. Recently, the appearance of the thermo-activated delay fluorescence (TADF) which may through inverse upper conversion to obtain the delay fluorescence used in OLED, leads to a wonderful perspective in this field. In this review, several basic problems are discussed in details concluding such as the electron excitation, excited state splitting, exchange energy between singlet and triplet states, the recombination of charge carries, the formation of exciton, and the charge transfer(CT) problems in pure organic and organo-transition metal complex, etc.

Key words: organic light-emitting diode (OLED), thermo-activated delay fluorescence (TADF), exchange energy of electron, Inverse inter-system crossing and upper conversion, charge transfer (CT) state

WU Shikang. The Triplet State Conversion to Singlet Excited State in OLED[J]. Imaging Science and Photochemistry, 2014, 32(3): 217-237.

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