title: Constructing a Novel Dendron for a Self-Host Blue Emitter with Thermally Activated Delayed Fluorescence: Solution-Processed Nondoped Organic Light-Emitting Diodes with Bipolar Charge Transfer and Stable Color Purity.
abstract: Self-host thermally activated delayed fluorescence (TADF) materials have recently been identified as effective emitters for solution-processed nondoped organic light-emitting diodes (OLEDs). However, except for the carbazole unit, few novel dendrons have been developed to build self-host TADF emitters. This study reports two self-host blue materials, tbCz-SO and poCz-SO, with the same TADF emissive core and different dendrons. The influence of the peripheral dendrons on the photophysical properties and electroluminescent performances of the self-host materials were systematically investigated. The transient fluorescence and electroluminescence spectra indicated that the diphenylphosphoryl carbazole units could effectively encapsulate the emissive core to reduce the concentration quenching effect and to enhance reverse intersystem crossing. By using tbCz-SO and poCz-SO as host-free blue emitters, the performance of the solution-processed nondoped OLED device demonstrated that a more balanced charge transfer from the bipolar dendrons would offer a better current efficiency of 10.5 cd A-1and stable color purity with Commission Internationale de L'Eclairage units of (0.18, 0.27).
authors.affiliation: School of Chemical Engineering, Huaihai Institute of Technology, Cang Wu Road 59, China) Lianyungang 222005.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Ban
authors.affiliation: School of Chemistry and Chemical Engineering, Southeast University, Si Pai Lou 2, China) Nanjing 211189.
authors.forename: Baoping
authors.initials: B
authors.lastname: Lin
authors.affiliation: School of Chemistry and Chemical Engineering, Southeast University, Si Pai Lou 2, China) Nanjing 211189.
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.affiliation: School of Chemistry and Chemical Engineering, Southeast University, Si Pai Lou 2, China) Nanjing 211189.
authors.forename: Yueming
authors.initials: Y
authors.lastname: Sun
keywords: blue emission; dendrons; fluorescence; organic light-emitting diodes; photophysics