|Événements du mois|
L'équipe "Chimie et électrochimie des matériaux" de l'Institut Jean Lamour accueille Sandra Schaefer (Technical University Darmstadt) pour un séminaire intitulé :
"Nanostructure research at the Technical University Darmstadt"
Date et lieu :
Lundi 22 juin 2015 à 11h
Institut Jean Lamour
Salle département chimie
One-dimensional nanostructures, such as metal nanowires, nanorods or nanotubes became of major interest over the last years. The reason for that are their unique applications in mesoscopic physics and fabrication of nanoscale devices. This opens a wide field of application for those structures dependent on the structure material.
The one-dimensional nanostructures are synthesized by a template method in which porous membranes such as anodized aluminum oxide (AAO) or ion-track etched polymers are used as templates. Then, those templates are filled with a metal or metal oxide. Therefore, several synthesis methods have been established. The probably most important and well-known synthetic route towards one-dimensional metal nanostructures is electrodeposition. Regarding this synthesis process, an externally applied electric field is necessary to run the deposition reaction. An alternative way to synthesize metal nanostructures in which the driving force is not an external electrical field are the chemical deposition methods such as electroless plating. This process is an autocatalytic method to deposit metallic films onto an activated template surface. Therefore, e.g. palladium nanoparticles are precipitated on the surface of an ion track-etched polymer template. These are the seeding particles, on which the deposition of the metal film begins. For the deposition of Fe, Ni or Co potent reducing agents such as hydrazine, dimethylaminoborane (DMAB), sodium borohydride or hypophosphite have been used. For noble metals such as Ag, Au or Pt less harsh reducing agents can be used, such as tartrates or ascorbic acid.
Our group in Darmstadt is specialized in the development of new electroless plating methods for the synthesis of nanostructures. Those nanostructures find application in catalytics, sensor techniques, magnetics and micromechanics.