Details
| Original language | English |
|---|---|
| Pages (from-to) | 1179-1188 |
| Number of pages | 10 |
| Journal | Journal of Materials Science |
| Volume | 45 |
| Issue number | 5 |
| Early online date | 4 Dec 2009 |
| Publication status | Published - Mar 2010 |
Abstract
For the first time, magnus green salt (MGS, [Pt(NH3) 4][PtCl4]) fibers precipitated by solvent modification have been employed as a structure-directing modifier to synthesize single silica and silica/titania microtubes via a sol-gel process. In the case of titania tubes, tetraethylorthosilicate must be used as a capping agent to hinder the aggregation of primary MGS fibers and to serve as a protective layer against thermal stress during the metal salt fiber reduction. This implies that SiO 2/TiO2 tubes result. The synthesized tubular materials were imaged by scanning and transmission electron microscopy, while their composition was determined by energy dispersive X-ray analysis and thermogravimetric analysis. Crystallinity and thermal stability of the tube walls were studied using X-ray diffraction analysis. The obtained oxide tubes possess high aspect ratios (80-200) because they are up to 60 μm in length, but only 300-700 nm in thickness. The key aspects of the synthesis approach are that the templating MGS fibers control the internal diameter of the oxide tubes, while the synthesis conditions control their wall thickness. The suggested method is a simple approach which produces, at low temperatures, very long oxide tubes with a very high amount of Pt (48-51 wt%) directly incorporated inside the tubes. To the best of our knowledge, filling of SiO2 or SiO 2/TiO2 nanotubes with such a dense population of Pt metal nanoparticles has not been demonstrated so far; our own experiments with [Pt(NH3)4](HCO3)2 as templating salt formed only tubes containing about 40 wt% Pt and were only about 20 μm long. The now formed more Pt-rich tubes are expected to have vivid applications in (photo)catalysis and in fabricating novel devices, such as nano- or sub-microcables.
ASJC Scopus subject areas
- Materials Science(all)
- General Materials Science
- Engineering(all)
- Mechanics of Materials
- Engineering(all)
- Mechanical Engineering
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In: Journal of Materials Science, Vol. 45, No. 5, 03.2010, p. 1179-1188.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Ultra-long SiO2 and SiO2/TiO2 tubes embedded with Pt nanoparticles using magnus green salt as templating structures
AU - Aresipathi, Catherine
AU - Feldhoff, Armin
AU - Wark, Michael
N1 - Funding Information: Acknowledgements The authors express their sincere gratitude to Dr. Falk Heinroth (Institute of Inorganic Chemistry, Leibniz University of Hannover) for performing TGA analysis and Prof. Dr. Jürgen Caro (Institute of Physical Chemistry, Leibniz University of Hannover) for general support. The work was financially supported by Deutsche Forschungsgemeinschaft (DFG, WA 1116-16).
PY - 2010/3
Y1 - 2010/3
N2 - For the first time, magnus green salt (MGS, [Pt(NH3) 4][PtCl4]) fibers precipitated by solvent modification have been employed as a structure-directing modifier to synthesize single silica and silica/titania microtubes via a sol-gel process. In the case of titania tubes, tetraethylorthosilicate must be used as a capping agent to hinder the aggregation of primary MGS fibers and to serve as a protective layer against thermal stress during the metal salt fiber reduction. This implies that SiO 2/TiO2 tubes result. The synthesized tubular materials were imaged by scanning and transmission electron microscopy, while their composition was determined by energy dispersive X-ray analysis and thermogravimetric analysis. Crystallinity and thermal stability of the tube walls were studied using X-ray diffraction analysis. The obtained oxide tubes possess high aspect ratios (80-200) because they are up to 60 μm in length, but only 300-700 nm in thickness. The key aspects of the synthesis approach are that the templating MGS fibers control the internal diameter of the oxide tubes, while the synthesis conditions control their wall thickness. The suggested method is a simple approach which produces, at low temperatures, very long oxide tubes with a very high amount of Pt (48-51 wt%) directly incorporated inside the tubes. To the best of our knowledge, filling of SiO2 or SiO 2/TiO2 nanotubes with such a dense population of Pt metal nanoparticles has not been demonstrated so far; our own experiments with [Pt(NH3)4](HCO3)2 as templating salt formed only tubes containing about 40 wt% Pt and were only about 20 μm long. The now formed more Pt-rich tubes are expected to have vivid applications in (photo)catalysis and in fabricating novel devices, such as nano- or sub-microcables.
AB - For the first time, magnus green salt (MGS, [Pt(NH3) 4][PtCl4]) fibers precipitated by solvent modification have been employed as a structure-directing modifier to synthesize single silica and silica/titania microtubes via a sol-gel process. In the case of titania tubes, tetraethylorthosilicate must be used as a capping agent to hinder the aggregation of primary MGS fibers and to serve as a protective layer against thermal stress during the metal salt fiber reduction. This implies that SiO 2/TiO2 tubes result. The synthesized tubular materials were imaged by scanning and transmission electron microscopy, while their composition was determined by energy dispersive X-ray analysis and thermogravimetric analysis. Crystallinity and thermal stability of the tube walls were studied using X-ray diffraction analysis. The obtained oxide tubes possess high aspect ratios (80-200) because they are up to 60 μm in length, but only 300-700 nm in thickness. The key aspects of the synthesis approach are that the templating MGS fibers control the internal diameter of the oxide tubes, while the synthesis conditions control their wall thickness. The suggested method is a simple approach which produces, at low temperatures, very long oxide tubes with a very high amount of Pt (48-51 wt%) directly incorporated inside the tubes. To the best of our knowledge, filling of SiO2 or SiO 2/TiO2 nanotubes with such a dense population of Pt metal nanoparticles has not been demonstrated so far; our own experiments with [Pt(NH3)4](HCO3)2 as templating salt formed only tubes containing about 40 wt% Pt and were only about 20 μm long. The now formed more Pt-rich tubes are expected to have vivid applications in (photo)catalysis and in fabricating novel devices, such as nano- or sub-microcables.
UR - http://www.scopus.com/inward/record.url?scp=76649137955&partnerID=8YFLogxK
U2 - 10.1007/s10853-009-4062-y
DO - 10.1007/s10853-009-4062-y
M3 - Article
AN - SCOPUS:76649137955
VL - 45
SP - 1179
EP - 1188
JO - Journal of Materials Science
JF - Journal of Materials Science
SN - 0022-2461
IS - 5
ER -