journal article·2025-01-08Open access

Layer-by-layer assembly yields thin graphene films with near theoretical conductivity

Oran Cassidy, Kevin Synnatschke, Jose M. Munuera, Cian Gabbett, Tian Carey, Luke Doolan, Eoin Caffrey, Jonathan N. Coleman

Abstract

Thin films fabricated from solution-processed graphene nanosheets are of considerable technological interest for a wide variety of applications, such as transparent conductors, supercapacitors, and memristors. However, very thin printed films tend to have low conductivity compared to thicker ones. In this work, we demonstrate a simple layer-by-layer deposition method which yields thin films of highly-aligned, electrochemically-exfoliated graphene which have low roughness and nanometer-scale thickness control. By optimising the deposition parameters, we demonstrate films with high conductivity (1.3 × 10 5 S/m) at very low thickness (11 nm). Finally, we connect our high conductivities to low inter-nanosheet junction resistances (R J ), which we estimate at R J ~ 1kΩ.
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Research context

OpenAlex topics: Graphene research and applications · Supercapacitor Materials and Fabrication · ZnO doping and properties

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