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Photoluminescence spectra of thermally activated delayed fluorescence emitter


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Photoluminescence spectra of thermally activated delayed fluorescence emitter
Zhang YangWang WeiChen WeiYang XiaoLi Heng
School of Electronic Engineering and Optoelectronic Technology,Nanjing University of Science and Technology,Nanjing 210094,China
thermally activated delayed fluorescence emitter photoluminescence molecular interaction temperature molecular structure
In order to understand the influence of molecular structure and molecular interaction on the light physical processes of the thermally activated delayed fluorescence emitter,photoluminescence spectroscopy of thermally activated delayed fluorescence(TADF)emitter,namely,2,4,5,6-tetrakis(carbazol-9-yl)-1,3-dicyanobenzene(4CzIPN)and its derivative,2,3,5,6-tetrakis(3,6-diphenylcarbazol-9-yl)-1,4-dicyanobenzene(4CzTPN-Ph)are studied.In 4CzIPN film,the photoluminescence intensity increases unexpectedly when temperature increases at 280K,which is ascribed to be the thermally weakening of molecular interaction.On the contrary,no such phenomenon is observed in 4CzTPN-Ph film.The results indicate that the molecular structure can be modified to adjust to molecular interaction's influence on photoluminescence processes,in order to enhance the efficiency of corresponding light emission diodes.


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Last Update: 2016-06-30