A simple technique for the fabrication of zinc oxide-PEDOT:PSS nanocomposite thin film for OLED application

•A novel method for in-situ synthesis of zinc oxide nanorods in polymer matrix.•Stable thin films of ZnO-PEDOT:PSS nanocomposite were fabricated and tested as HTL in OLEDs.•4.5 times enhancement in luminance with modified HIL of ZnO NR-PEDOT:PSS film.•Current efficiency was improved 11.03 cd/A and power efficiency was enhanced 2.4 times in the presence of ZnO nanorods.

We report in-situ synthesis of zinc oxide nanorods on pre-seeded substrates with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) matrix resulting in thin films of ZnO nanorods (NR)-PEDOT:PSS nanocomposite. Prepared ZnO-PEDOT:PSS nanocomposite films were characterized by X-ray diffraction (XRD) and scanning electron microscopy. Wurtzite crystal structure of ZnO was confirmed by the XRD analysis and SEM images indicated the successful incorporation of ZnO in polymer matrix. These nanocomposite thin films were then used as hole injecting layers (HILs) in organic light emitting diodes. Devices were prepared using nanocomposite film and studied using current density-voltage (J-V) characteristics and electroluminescence (EL) measurements. Luminance was enhanced by 4.5 times with modified HIL of ZnO NR-PEDOT:PSS film as compared to the reference device with pristine PEDOT:PSS as HIL. Current efficiency was improved from 4.62 cd/A to 11.03 cd/A and power efficiency was enhanced by 2.4 times in the presence of ZnO nanorods.

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