Dr. Hai Le The – University of Twente
Noble metal nanoparticles and their interfacial interaction with ceramic supports upon UV-ozone treatment
Periodic noble metal nanoparticles offer a wide spectrum of applications including chemical and biological sensors, optical devices, and model catalysts due to their extraordinary properties. The particle size and shape, composition, oxidation state, and the interaction of the particle with its support are attributed to strongly affect the catalytic activity simultaneously. However, under chemical reactions, metallic nanoparticles have found to be unstable due to the sintering of particles which results in blocking of active sites and deactivation. Therefore, for catalysis studies, highly ordered and uniform metallic nanoparticles on support substrates are highly demanded as better control in the uniformity and distribution of the metallic nanoparticles leads to better controlled properties. In this presentation, a robust fabrication method that allows rapid patterning of highly ordered noble metal (Au and Pt) nanoparticles supported directly on oxidized silicon (SiO2) substrates is presented. In addition, a study on their interaction with ceramic supports upon UV-ozone treatment is also given. A strong adhesion of Au micro/nanostructures to SiO2 has been found after a post-deposition UV-ozone treatment. The observed adhesion improvement can be explained as polarization-induced increased strength of Aud–Sid+ bonds at the Au-SiO2 interface due to the formation of a gold oxide monolayer on the Au surface by the UV-ozone treatment.