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Synthesis and study of carbon/TiO2 and carbon/TiO2 core–shell micro-/nanospheres with increased density

Published online by Cambridge University Press:  29 October 2012

Cynthia Papo ,
Zikhona Tetana ,
Paul Franklyn  and
Sabelo Mhlanga
Cynthia Papo
Affiliation:
Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Wits, 2050, Johannesburg, South Africa
Zikhona Tetana
Affiliation:
Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Wits, 2050, Johannesburg, South Africa; and DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, Johannesburg, South Africa
Paul Franklyn
Affiliation:
Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Wits, 2050, Johannesburg, South Africa
Sabelo Mhlanga*
Affiliation:
Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Wits, 2050, Johannesburg, South Africa; and DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, Johannesburg, South Africa
*
a)Address all correspondence to this author. e-mail: Sabelo.Mhlanga@wits.ac.za
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Abstract

Nanosized graphitic carbon provides high selectivity and stability of catalysts. However, the carbon is very light when used as a support, even when loaded with metals. To counteract this problem, carbon/TiO2 core–shell structures were synthesized via chemical vapor deposition (CVD) using a single source precursor to increase its density, while maintaining a high surface area and stability of the materials. The diameter of the carbon/TiO2 spheres could be controlled from 2 μm to 200 nm by varying the flow rate of nitrogen. TEM analysis revealed that a fraction of the spheres exhibited a core–shell structure, with a faint carbon shell surrounding the TiO2 sphere. The density of the carbon/TiO2structures was 0.70 g/mL, which is four times higher than that of pure carbon nanotubes and spheres synthesized by CVD.

Type
Articles
Information
Journal of Materials Research , Volume 28 , Issue 3: Focus Issue: Titanium Dioxide Nanomaterials , 14 February 2013 , pp. 440 - 448
Copyright
Copyright © Materials Research Society 2012

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References

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