Regensburg 2019 – wissenschaftliches Programm
O 64.11: Poster
Mittwoch, 3. April 2019, 17:45–20:00, Poster B1
The effect of temperature in plasmon driven reactions — •Wouter Koopman1, Radwan Sarhan1,2, Ferenc Liebig3, Jan Pudell1, Marc Herog1, Matthias Rössle4, Thomas Schmid2,5, Sebastian Schmitt4, Felix Stete1,2, Clemens Schmitt6, Joachim Koetz3, and Matias Bargheer1,4 — 1Institute of Physics and Astronomy, University of Potsdam — 2School of Analytical Sciences Adlershof, Humboldt-Universität zu Berlin — 3Institute of Chemistry, University of Potsdam — 4Helmholtz Zentrum Berlin — 5Federal Institute for Materials Research and Testing, Berlin — 6Max Planck Institute of Colloids and Interfaces, Potsdam
Metal nanoparticles form potent nanoreactors, driven by the optical generation of energetic electrons and nanoscale heat. The relative influence of these two factors on nanoscale chemistry is strongly debated. We investigate the temperature dependence of the dimerization of 4-NTP into DMAB adsorbed on goldnanoflowers.Static X-ray diffraction and Raman thermometry indicate a temperature increase of the nanoparticles in the order of 150K. A much higher temperature of the DMAB molecules, around 500K, is regarded as sign of vibrational activation of the molecules by electron injection. The role of the electron injection is corroborated by the observation of an intensity threshold for the photo-driven reaction. On the other hand, a comparison between measurements of the reaction kinetics at different temperatures and different intensities indicate, that an increased reaction rate at higher light intensities could be rooted in a higher temperatures of the particles.