Vertical ZnO nanowires/graphene hybrids for transparent and flexible field emission

Jin Ok Hwang, Duck Hyun Lee, Ju Young Kim, Tae Hee Han, Bong Hoon Kim, Moonkyu Park, Kwangsoo No, Sang Ouk Kim

Research output: Contribution to journalArticle

208 Scopus citations


We present a transparent and flexible optoelectronic material composed of vertically aligned ZnO NWs grown on reduced graphene/PDMS substrates. Large-area reduced graphene films were prepared on PDMS substrates by chemical exfoliation from natural graphite via oxidative aqueous dispersion and subsequent thermal reduction. ZnO NWs were hydrothermally grown on the reduced graphene film substrate and maintained their structural uniformity even in highly deformed states. The electrical contact between semiconducting ZnO NWs and the metallic graphene film was straightforwardly measured by electric force microscopy (EFM). It shows a typical metal-semiconductor ohmic contact without a contact barrier. Owing to the mechanical flexibility, transparency, and low contact barrier, the ZnO NWs/graphene hybrids show excellent field emission properties. Low turn-on field values of 2.0 V μm-1, 2.4 V μm-1, and 2.8 V μm-1 were measured for convex, flat, and concave deformations, respectively. Such variation of field emission properties were attributed to the modification of ZnO NWs emitter density upon mechanical deformation.

Original languageEnglish
Pages (from-to)3432-3437
Number of pages6
JournalJournal of Materials Chemistry
Issue number10
StatePublished - 2011 Mar 14

Fingerprint Dive into the research topics of 'Vertical ZnO nanowires/graphene hybrids for transparent and flexible field emission'. Together they form a unique fingerprint.

  • Cite this

    Hwang, J. O., Lee, D. H., Kim, J. Y., Han, T. H., Kim, B. H., Park, M., No, K., & Kim, S. O. (2011). Vertical ZnO nanowires/graphene hybrids for transparent and flexible field emission. Journal of Materials Chemistry, 21(10), 3432-3437.