Feasible Modification of PEDOT:PSS by Poly(4-styrenesulfonic acid): A Universal Method to Double the Efficiencies for Solution-Processed Organic Light-Emitting Devices

Yepeng Xiang; Guohua Xie; Qian Li; Longjian Xue; Qian Xu; Junfa Zhu; Yang Tang; Shaolong Gong; Xiaojun Yin; Chuluo Yang

doi:10.1021/acsami.9b09346

Feasible Modification of PEDOT:PSS by Poly(4-styrenesulfonic acid): A Universal Method to Double the Efficiencies for Solution-Processed Organic Light-Emitting Devices

ACS Appl Mater Interfaces. 2019 Aug 14;11(32):29105-29112. doi: 10.1021/acsami.9b09346. Epub 2019 Jul 31.

Authors

Yepeng Xiang^{1

2}, Guohua Xie¹, Qian Li³, Longjian Xue³, Qian Xu⁴, Junfa Zhu⁴, Yang Tang¹, Shaolong Gong¹, Xiaojun Yin², Chuluo Yang^{1

2}

Affiliations

¹ Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Department of Chemistry , Wuhan University , Wuhan 430072 , China.
² Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering , Shenzhen University , Shenzhen 518060 , China.
³ School of Power and Mechanical Engineering & The Institute of Technological Science , Wuhan University , South Donghu Road 8 , Wuhan 430072 , China.
⁴ National Synchrotron Radiation Laboratory , University of Science and Technology of China , Hefei 230029 , Anhui , China.

PMID: 31321974
DOI: 10.1021/acsami.9b09346

Abstract

A feasible, universal, and low-cost strategy for solution-processed organic light-emitting diodes (OLEDs) was provided to significantly enhance the electroluminescent performances. The commercially available poly(4-styrenesulfonic acid) (PSSA) aqueous solution was mixed into poly(styrene sulfonic acid)-doped poly(3,4-ethylenedioxythiphene) (PEDOT:PSS) to modify its chemical and physical properties. The corresponding work function can be easily elevated from 5.04 to 5.63 eV. The modification of PEDOT:PSS by PSSA is found to be a universal method to demonstrate highly efficient OLEDs with different solution-processed host/emitter combinations, covering phosphorescent and thermally activated delayed fluorescence devices. The benchmarking solution-processed OLEDs based on 2,4,5,6-tetrakis(carbazol-9-yl)-1,3-dicyanobenzene and bis[2-(4,6-difluorophenyl)pyridinato-C²,N](picolinato)iridium(III) achieved the maximum external quantum efficiencies of 26.6 and 22.4%, respectively, simply by modifying PEDOT:PSS with PSSA, corresponding to the improvement factors of 2.7 and 2.2. It is confirmed that such performances originate simultaneously from reduced interfacial fluorescence quenching, elevated work function, and reduced lateral conduction of the commonly used PEDOT:PSS (Clevios P VP Al 4083).

Keywords: PEDOT:PSS; fluorescence quenching; full colors; solution-processed OLEDs; work function.