Name of presentation

1
Name of presentation
CHEMICAL SYNTHESIS OF GRAPHENE FOR DYE SOLAR
CELLS ELECTRODES
Presenter F. T. Thema

• Organisation name

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Overview

• Introduction
• Aim and Objectives
• Production of graphene
• Graphene oxide film preparation
• Morphological properties of GO
• Spectroscopy of GO
• Conclusion
• Future work
• Acknowledgements
• References

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Introduction
Graphene Superlatives Thinnest imaginable
material largest surface area (2.700 m2 per
gram) Strongest material ever measured
(theoretical limit) Stiffness known material
(stiffer than diamond) Most stretchable crystal
(up to 20 elasticity) Record thermal
conductivity (outperforming diamond) Highest
current density at room T (106 times of
copper) Completely impermeable (even He atoms
cannot squeeze through)

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Aim and Objectives

• Aim
• To use the unusual and unique properties of
  graphene as transparent and conductive electrode
  to be used as TCO equivalent.
• Objectives
• Use modified Hummers method to
  synthesize/engineer large graphene thin films
  with different properties (3-5 nm)
• Use reduced graphene oxide in solar cells

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Methods of producing graphene
Production of graphene

• K.S. Novoselov et al Nature 2012, 490, 192200 

K.S. Novoselov et al Nature 2012, 490, 192200 
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Graphene Oxide Film Preparation
Graphite Flakes
GO suspension in water
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Morphological Properties of GO
Optical Microscopy
Scanning Electron Microscopy
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Raman characterization of GO and rGO
Material ID/IG
GO 1.2
r-GO (Annealing) 0.95
r-GO (Our Method) 0.96
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Conclusion

• Graphene oxide solution was produced
• Vacuum filtration was used to produce large area
  graphene oxide films
• The graphene oxide was reduced to produce
  graphene with suitable properties for use as a
  TCO

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Future work

• Use different methods to reduce graphene oxide to
  graphene
• Use the large area graphene films as transparent
  conductors in solar photovoltaic devices

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Acknowledgements

• iThemba LABS
• Unisa
• Philip - iThemba LABS Radiobiology
• Stephen Nzioki B , Dr F. Cumings B. Sone
  UWC
• Chris B iThemba LABS
• Takalani Madima - Unisa
• G Bepete N.J. Coville WITS University

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Related publications

• F.T. Thema et.al Synthesis and characterization
  of graphene thin films by chemical reduction
  exfoliated and intercalated graphite oxide. J.
  Chem. (2013) DOI 10.1155/2013/150536.
• F.T. Thema et al Synthesis and characterization
  of graphene thin films via Hummers Method.
  Technical Proceedings of the Nano Science and
  Technology Institute, (2012) 1, 13-16. ISBN
  678-1-4665-6274-5.
• Ezekiel D. Dikio, Force T. Thema et. al One-step
  reduction, characterization and magnetic
  behaviour of exfoliated graphene oxide. J. Mater.
  Sci. Pol. (2012) DOI 10.2478/s13536-012-0068-2.
• Abdullahi M. Farah, Force T. Thema et.al
  Electrochemical detection of hydrogen peroxide
  based on graphene oxide/Prussian blue modified
  glassy carbon electrode. Int. J. Electrochem.
  Sci. 7(6) (2012) 5069 5083.
• E.D. Dikio, F.T. Thema, et. al Synthesis of
  carbon nanotubes by catalytic decomposition of
  ethane using Co-Zn-Al catalyst. Inter. J.
  Nanotech Appl, vol 4, 2 (2010) 117-124.

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I thank you !!!