Quasi-freestanding graphene-on-single walled carbon nanotube electrode for applications in organic light-emitting diode

Abstract

An air-stable transparent conductive film with "quasi- freestanding" graphene supported on horizontal single walled carbon nanotubes (SWCNTs) arrays is fabricated. The sheet resistance of graphene films stacked via layer-by-layer transfer (LBL) on quartz, and modified by 1-Pyrenebutyric acid N-hydroxysuccinimide ester (PBASE), is reduced from 273 Ω/sq to about 76 Ω/sq. The electrical properties are stable to heat treatment (up to 200 °C) and ambient exposure. Organic light-emitting diodes (OLEDs) constructed of this carbon anode (T ≈ 89.13% at 550 nm) exhibit ≈88% power efficiency of OLEDs fabricated on an ITO anode (low turn on voltage ≈3.1 eV, high luminance up to ≈29 490 cd/m2, current efficiency ≈14.7 cd/A). Most importantly, the entire graphene-on-SWCNT hybrid electrodes can be transferred onto plastic (PET) forming a highly-flexible OLED device, which continues to function without degradation in performance at bending angles >60°. A high efficiency organic light emitting diode (OLED) is fabricated on a flexible and transparent electrode made from "quasi-freestanding" graphene supported on laterally aligned single walled carbon nanotubes, and doped with 1-pyrenebutyric acid N-hydroxysuccinimide ester. The all-carbon electrode exhibits highly stable sheet resistance of 76 Ω/square. © 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.