Solution phase production of graphene with controlled thickness via density differentiation

Alexander A. Green, Mark C. Hersam

Research output: Contribution to journalArticle

572 Scopus citations


Graphene flakes with controlled thicknesses are isolated in solution using density gradient ultracentrifugation. These stable graphene dispersions are produced using the bile salt sodium cholate, which promotes graphite exfoliation and results in graphene-surfactant complexes having buoyant densities that vary with graphene thickness. The sorted graphene flakes are characterized using atomic force microscopy and Raman spectroscopy. Graphene dispersions produced using density differentiation offer superior performance in transparent conductors than those produced using conventional sedimentation-based centrifugation techniques.

Original languageEnglish (US)
Pages (from-to)4031-4036
Number of pages6
JournalNano Letters
Issue number12
StatePublished - Dec 9 2009


ASJC Scopus subject areas

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

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