Synthesis of heterobimetallic Sn/Zn-alkoxides and their controlled transformation to Amorphous Sn-doped ZnO or Zn2SnO4 nanocrystals
3rd EuCheMS (European Association for Chemical and Molecular Sciences)-Chemistry Congress, Nürnberg, Germany, 20 August - 02 September 2010, pp.34
- Publication Type: Conference Paper / Full Text
- City: Nürnberg
- Country: Germany
- Page Numbers: pp.34
- Akdeniz University Affiliated: Yes
Abstract
The reliable synthesis of well defined nano-materials by controlling defects and
morphology of the particles, as well as providing a high dispersion of the doping
elements in the matrix without other impurities, is one of the primary aims in material
chemistry. Zinc oxide (ZnO) can be regarded as a key material in engineering,
furthermore nanostructured ZnO is a important material for heterogeneous catalysis [1]
and semiconductive devices. [2] ZnO is a direct bandgap semiconductor (Eg = 3.30 eV
at room temperature) with a free exciton binding energy of 60 meV. [3] However, in
order to prepare nanocrystalline ZnO of high purity while maintaining control over the
composition, morphology (particle size and shape), porosity etc., a suitable synthetic
method is required. Traditionally ZnO nano-materials have been synthesized by
various techniques, such as flame pyrolysis of ZnO precursors [4] and the evaporation
and oxidation of elemental zinc. [5] However, these methods give rise to an
inhomogeneous particle shape distribution. To overcome this problem we employ the
Single Source Precursor (SSP) concept: In the first step a suitable organometallic
precursor is synthesized, which is in a second step, thermally decomposed into ZnO.
This precursor already contains all the information necessary for the inorganic
functional material. [6]
Currently we are focusing on the synthesis of defined heterobimetallic organozinc
alkoxides as potential molecular SSP for the preparation of heterometallic (doped)
ZnO materials. Interestingly doping ZnO with certain elements presents an effective
method to modify its electrical, optical and magnetic properties. In particular tin doped
zinc oxide (Sn@ZnO) are promising semiconductive materials. [7]
We present a novel technique for the successful synthesis of Sn/Zn-alkoxides with
different sterically demanding organic groups. Their thermal degradation leads to,
depending on the variation of the decomposition parameters and the organic groups,
different ZnO-based materials. We report how one SSP can easily lead, by controlled
decomposition, to different final materials with variable properties and applications.
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