Photothermal effects in plasmonic assisted photocatalysis: a parametric study

Abstract

Recently, it has been suggested that chemical reactions can be facilitated by using mm-scale composites of plasmonic metal nanoparticles on porous oxides. This effect was shown recently to be predominantly associated with the heating induced by illumination. In this study, we study the sensitivity of the temperature rise to various parameters. We show that, the temperature rise in photocatalysts is typically weakly-dependent on the illumination wavelength, pulse duration, particle shape, size and density but is strongly sensitive to the beam size and the host thermal conductivity. Our results indicate that although plasmonic nanoparticles are thought of as nanoscale heat sources, the heat generation from which does not differ so much from macroscopic heat sources. On a more general level, this work is instrumental in uprooting some common misconceptions associated with the role of thermal effects in applications that rely on heat generation from a large number of particles.