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Name (Title):
Norifusa Satoh (Research Associate (Non-tenured))
Affiliation:
Department of Chemistry, Keio University
Address:
3-14-1 Hiyoshi Yokohama 223-8522, Japan
Email: satoh@chem.keio.ac.jp
Home Page: http://www.educ.cc.keio.ac.jp/~kylab/
Presentation Title:
Stepwise metal assembling dendrimers and the application to organic electronics devices and
atom technology for novel metal oxide materials
Abstract:
There has never been nanotechnology to
control particle size according to the number of
the component. We succeeded the atomic level
size-control of TiO2 particles (both of rutile and
anatase) with a standard deviation of 0.2 nm,
using fine controlled metal assembly on a
phenylazomethine dendrimer (DPA G4, Fig.
1A) [1].
The number and location of the loaded metal
ions tend to be random within the previous
dendrimers, resulting in a wide distribution of
the templated particle in size. However, the
number and location of metal ions can be finely
controlled in DPA G4 because of the πconjugated
rigid framework. The rigid
framework maintains the desirable dendritic and
cascade structure [2, 3]. It is reflected on the
cascade in the imine basicity on each layer.
Poster Session PM-27
Fig. 1 A. Phenylazomethine dendrimer. B. OLED.
C. DSSC. D. Scheme of Q-size TiO2.
The π-conjugated dendrimers with a triphenylamine core are also useful for the application to
organic electronics devices, such as organic light emitting diodes (OLED, Fig. 1B) and dyesensitized
solar cells (DSSC, Fig. 1C). The electron transfer through the π-conjugated
framework contributes the control of the electron vector, resulting in higher cell performances [2,
3].
The fine size-control using the dendrimer template on substrate (Fig. 1D) revealed the
quantum size effect in TiO2. The energy gap of the obtained particles showed a blue shift as
decreasing in size and a difference in energy between the anatase and rutile forms. The sizedependency
and difference between the crystal forms in bandgap energy is described using a
semi-empirical effective mass approximation [1].
References:
[1] N. Satoh, T. Nakashima, K. Kamikura, K. Yamamoto, Nature Nanotech., 3, 106–111 (2008).
[2] N. Satoh, J.-S. Cho, M. Higuchi, K. Yamamoto, J. Am. Chem. Soc., 125, 8104–8105 (2003).
[3] N. Satoh, T. Nakashima, K. Yamamoto, J. Am. Chem. Soc., 127, 13030–13038 (2005).
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