Highly conductive sandwich-structured CNT/PEDOT:PSS/CNT transparent conductive films for OLED electrodes

  • Ze-Zeng Gu
  • Ying Tian
  • Hong-Zhang GengEmail author
  • Danielle S. Rhen
  • Anita Sagadevan Ethiraj
  • Xingcai Zhang
  • Li-Chao Jing
  • Tao Wang
  • Zi-Han Xu
  • Xiao-Tong Yuan
Original Article


Carbon nanotubes (CNTs) and poly(3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) were employed to prepare sandwich-structured CNT/PEDOT:PSS/CNT transparent conductive films (TCFs) on flexible polyethylene terephthalate (PET) substrate by a spraying method. Based on the film morphology, we suggest that the CNTs were embedded in PEDOT:PSS. The structured film was more stable and did not peel off during post-processing nitric acid treatment. Ethylene glycol (EG) was used to improve the conductivity of the film, and the best ratio of PEDOT:PSS to EG was 10:5. XPS and Raman spectroscopy studies revealed that the non-conductive sodium dodecylbenzene sulfonate and PSS were removed during the nitric acid treatment. TCF sheet resistance as low as 95.15 Ω/sq at 87.72% transmittance (at a wavelength of 550 nm) was obtained. When the CNT/PEDOT:PSS/CNT-TCF was used as an anode in an organic light emitting diode, the high luminance of the device was 1598 cd/cm2 at 14 V, and the maximum current efficiency was 1.5 cd/A at 13 V.


Transparent conductive films PEDOT:PSS Carbon nanotubes OLED 



The authors gratefully acknowledge financial support from the Natural Science Foundation of Tianjin China (Grant No. 15JCZDJC37900) and the Science and Technology Plans of Tianjin China (Grant No. 17PTSYJC00050).

Compliance with ethical standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.


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Copyright information

© King Abdulaziz City for Science and Technology 2019

Authors and Affiliations

  1. 1.Tianjin Key Laboratory of Advanced Fibers and Energy Storage, School of Material Science and EngineeringTianjin Polytechnic UniversityTianjinPeople’s Republic of China
  2. 2.Department of PhysicsVIT-AP UniversityAmaravatiIndia
  3. 3.John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeUSA

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