Surfactant-Free Single Layer Graphene in Water

Abstract

Dispersing graphite in water to obtain true (single layer) graphene (SLG) in bulk quantity in a liquid has been an unreachable goal for materials scientists in the last decade. Likewise, a diagnostic tool for identifying solubilized SLG in situ has been long awaited. Homogeneous stable dispersions of SLG in water are obtained by mixing graphenide (negatively charged graphene) solutions in tetrahydrofuran (THF) with degassed water and evaporating the organic solvent. In situ Raman spectroscopy of these aqueous dispersions shows all the expected characteristics of single layer graphene, including an intense 2D band of Lorentzian shape and linewidth of 28 cm-1. Transmission electron and atomic force microscopies on deposits confirm SLG character. The resulting additive-free stable water dispersions contain 0.16 mg/mL of SLG.

31 pages, main article has 17 pages, 4 figures, 2 Tables. Presented at Graphene Week (Manchester 2015); NN15, Thessaloniki, July 2015; TNT2015, Toulouse, Sept 2015; GraphITA, Bologna, Italy, Sept 2015; Intl Symp. on Synthetic Carbon Allotropes, Erlangen, Oct. 2015, GDR GNT, Aussois, Dec 2015, GraphIN, Zaragoza, Dec 3, 2015, IWEPNM (Kirchberg, Feb 2016), NanoSpain, Logroño (Spain) - March 2016

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Cited by in corpus (3)

• Post Graphene 2D Chemistry: The Emerging Field of Molybdenum Disulfide and Black Phosphorus Functionalization
• Solid lubrication by wet-transferred solution-processed graphene flakes: dissipation mechanisms and superlubricity in mesoscale contacts
• Surfactant-Free Polar-to-Non-Polar-Phase Transfer of Exfoliated MoS2 Two-Dimensional Colloids