Enhancing the efficiency of red TADF OLED by optimizing the guest-host matrix and charge balance engineering

TitleEnhancing the efficiency of red TADF OLED by optimizing the guest-host matrix and charge balance engineering
Publication TypeJournal Article
Year of Publication2020
AuthorsManoj, INaga Sai, Barah, D, Sahoo, S, Bhattacharyya, J, Ray, D
JournalSynthetic Metals
Volume270
Pagination116599
ISSN0379-6779
KeywordsCharge balance, Organic light emitting diode, Photoluminescence, Thermally activated delayed fluorescence
Abstract

Charge (electrons and holes) balance engineering is employed to demonstrate an enhancement in the performance of organic light emitting diodes (OLEDs) fabricated with a near infra red thermally activated delayed fluorescence (TADF) molecule 7,10-Bis(4-(diphenylamino)phenyl)-2,3-dicyanopyrazino phenanthrene (TPA-DCPP) . The emissive layer of the OLED comprises of a guest-host matrix. A detailed analysis of the choice of host that is to be employed in the guest-host matrix of the emissive layer of the OLED is presented. The doping concentration of the guest in the emissive layer is optimized by photoluminescence (PL) studies. A comparative analysis of 1,4,5,8,9,11-Hexaazatriphenylenehexacarbonitrile (HATCN) and Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) PEDOT: PSS as hole injection layers and their effect on device efficiency and charge balance in the emissive layer of the device stack is presented. From the study, a red TADF OLED with a maximum external quantum efficiency of 13.2% at a luminance of 1 cd/m2 is demonstrated.

URLhttp://www.sciencedirect.com/science/article/pii/S0379677920308511
DOI10.1016/j.synthmet.2020.116599