Regensburg 2007 – scientific programme
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O: Fachverband Oberflächenphysik
O 50: Particles and Clusters II
O 50.5: Talk
Thursday, March 29, 2007, 12:15–12:30, H38
Photochromic silver nanoparticles embedded in transition-metal oxides — •Alexander Sprafke, Florian Hallermann, Christoph Straka, Christian Dahmen, Matthias Wuttig, and Gero von Plessen — I. Insitute of Physics (IA), RWTH Aachen University, 52056 Aachen, Germany
Photochromic materials change their color when irradiated with light. We have recently reported on the photochromic transformation of silver nanoparticles embedded in titania. This transformation shows itself in a bleaching of the nanocomposite films at the wavelength of irradiation, and is probably caused by a plasmon-assisted photoemission of electrons from the resonantly excited Ag particles. In the present work, we investigate whether a photochromic effect can also be found in Ag nanoparticles embedded in other transition-metal oxides, such as ZrO2 and HfO2. We examine the changes of the optical spectra of the films during laser irradiation, and compare them to the findings of our previous studies on the Ag/TiO2 system. We discuss to what extent our model of the photochromic transformation can be applied to the Ag/ZrO2 and Ag/HfO2 films.