Nanofabrication of Electrochemical Transducer Using New Obserwed Phenomena During Anodization

abstract

English

The aim of presented work is the fabrication of Au nanorods further modified with TiO2 layer for the improving of electrode sensing properties due to increasing its specific surface. The impedimetric microsystem, which represents microhot-plate gas sensors, was prepared with the help of the deposition of POCl3 doped polysilicon heater and gold comb-like microstructures. The thin aluminum film (2 um) was deposited by evaporation method on the gold microstructures. The thin porous anodic alumina template was prepared by one-step oxidation process. First, the porous alumina grew up only on a conducted micro system, despite the theory of growing on all surface of aluminum layer. This fact was caused by differences between the thickness of aluminum on conductive layer and on the other areas. The second advantage is the skip phasing of oxide barrier chemical etching. The oxide barrier was successfully removed by continual anodization under the constant potential. Despite of the previous experience, it is not necessary to use phosphoric acid for dissolving the oxide barrier. Since all aluminum is consumed, the oxide barrier has started to be dissolved due to the high electric potential on interface conductor - oxide. Finally, the alumina template was used for the galvanic deposition of gold nanowires. Next step was aimed to the immobilization of TiO2 coatings by sol-gel technology starting from titanium tetrapropoxide precursor, ethanol as solvent and acetyl-acetone as stabilizing agent. Acknowledgment: This research was supported by Grant Agency of the Czech Republic under the contract GA102/06/1624. The CNM of Barcelona is also acknowledged for support delivery of the microhot-plate Microsystems.

anodization, microsensores, impedance spectroscopy, nanowires

HRDÝ, R.; HUBÁLEK, J.; VOROZHTSOVA, M.; DRBOHLAVOVÁ, J.

2. 8. 2009

Nanotoday

Singapur

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