Indirect optical transitions in hybrid spheres with alternating layers of titania and graphene oxide nanosheets

Opt Express. 2012 Dec 17;20(27):28801-7. doi: 10.1364/OE.20.028801.

Abstract

In this report, we studied the optical properties of hybrid spherical structures consisting of alternating nanosheets of titania (TiO(2)) and graphene oxide (GO) prepared by a layer-by-layer self-assembly technique. Compared to samples with only TiO(2) spheres or GO nanosheets, a blue-to-red light emission band emerges and persists in this novel composite material even after it was further reduced through microwave irradiation. From detailed time-resolved measurements and energy-level structure modeling, this unexpected fluorescent feature was attributed to the indirect optical transitions between TiO(2) and the localized sp(2) domains of GO in a charge-separated configuration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Computer Simulation
  • Graphite / chemistry*
  • Light
  • Membranes, Artificial*
  • Models, Chemical*
  • Nanoparticles / chemistry*
  • Nanoparticles / ultrastructure*
  • Oxides / chemistry
  • Particle Size
  • Scattering, Radiation
  • Titanium / chemistry*

Substances

  • Membranes, Artificial
  • Oxides
  • titanium dioxide
  • Graphite
  • Titanium