Conformational distortion in solution processable PVK:TcTa blends and the effect on extra warm white organic phosphorescent light emitting diodes
Document Type
Article
Publication Date
1-1-2019
Abstract
Organic semiconductors generally display significant conformational flexibility which results in significant energetic disorder. In this research, ultraviolet photoelectron spectra are compared with the Gaussian density of states obtained from the density functional theory on assembly of molecules optimized using molecular dynamic simulations. It was found out that spin-coated organic semiconductor, tris(4-carbazoyl-9-ylphenyl)amine (TcTa), displays significant conformational distortion from its minimum geometry with significant Gaussian broadening. Adding poly(vinylcarbazole) (PVK) into TcTa results in increased face to face stacking of carbazole moieties from PVK as evident from increased red-shifted of absorption of PVK. Despite reduction of energy barrier upon addition of TcTa into PVK, the current efficiency of the extra warm white organic light emitting diodes showed limited improvement probably from the increased triplet quenchers from the carbazole dimers. © 2019
Keywords
Conformational flexibility, Current efficiency, Gaussian broadening, Gaussian density of state, Poly(vinylcarbazole), Solution processable, Ultraviolet photoelectron spectra, White organic light emitting diodes
Divisions
CHEMISTRY,PHYSICS
Funders
Universiti Malaya Postgraduate Research Grant ( PG043-2015B ),MyBrainScholarship,University Malaya Research Grant UMRG Programme ( RP038A-17AFR )
Publication Title
Organic Electronics
Volume
74
Publisher
Elsevier