Nanoplasmonic Photothermal Heating and Near-Field Enhancements: A Comparative Survey of 19 Metals

Localized surface plasmon resonances optically excited in metallic nanoparticles (NPs) produce beneficial thermal and nonthermal effects. Non-thermal effects, such as enhancing and localizing fields on subwavelength scales and photo-generating hot carriers, have been extensively exploited, while interest in highly localized photothermal heating is reviving. Both effects may work together synergistically, such as increasing the efficiency of a photocatalytic process, or they may work against each other, such as accelerating the desorption of analytes in surface-enhanced spectroscopy. To compare how these effects depend on the composition and size of the NP, we report a quantitative survey of thermal and nonthermal properties in the visible-solar (1.7-4.1 eV) and ultraviolet (3.1-6.2 eV) ranges for 19 metals, including conventional plasmonic materials (gold, silver, copper), an alkaline earth metal (magnesium), post-transition metals (aluminum, gallium, indium), and a wide variety of transition metals. Figures of merit that reflect the resistive losses and electric field enhancement factor of the NPs were used in this comparative analysis.