Silicon nanowire arrays-induced graphene oxide reduction under UV irradiation

Nanoscale. 2011 Nov;3(11):4662-9. doi: 10.1039/c1nr10970g. Epub 2011 Sep 29.

Abstract

This paper reports on efficient UV irradiation-induced reduction of exfoliated graphene oxide. Direct illumination of an aqueous solution of graphene oxide at λ = 312 nm for 6 h resulted in the formation of graphene nanosheets dispersible in water. X-Ray photoelectron spectroscopy (XPS), UV-vis spectroscopy, atomic force microscopy (AFM) and electrochemical measurements (cyclic voltammetry and electrochemical impedance spectroscopy) suggest a restoration of the sp(2) carbon network. The results were compared with graphene nanosheets prepared by photochemical irradiation of a GO aqueous solution in the presence of hydrogenated silicon nanowire (SiNW) arrays or silicon nanowire arrays decorated with silver (SiNW/Ag NPs) or copper nanoparticles (SiNW/Cu NPs). Graphene nanosheets obtained by illumination of the GO aqueous solution at 312 nm for 6 h in the presence of SiNW/Cu NPs exhibited superior electrochemical charge transfer characteristics. This is mainly due to the higher amount of sp(2)-hybridized carbon in these graphene sheets found by XPS analysis. The high level of extended conjugated carbon network was also evident by the water insoluble nature of the resulting graphene nanosheets, which precipitated upon photochemical reduction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electric Conductivity
  • Graphite / chemistry*
  • Graphite / radiation effects*
  • Macromolecular Substances / chemistry
  • Materials Testing
  • Molecular Conformation
  • Nanostructures / chemistry*
  • Nanostructures / radiation effects
  • Nanostructures / ultrastructure
  • Oxides / chemistry
  • Oxides / radiation effects
  • Particle Size
  • Silicon / chemistry*
  • Silicon / radiation effects*
  • Surface Properties
  • Ultraviolet Rays

Substances

  • Macromolecular Substances
  • Oxides
  • Graphite
  • Silicon