Surface Plasmon Aided Ethanol Dehydrogenation Using Ag-Ni Binary Nanoparticles

Abstract

Plasmonic metal nanoparticles absorb light energy and release the energy through radiative or nonradiative channels. Surface catalytic reactions take advantage of the nonradiative energy relaxation of plasmons with enhanced activity. Particularly, binary nanoparticles are interesting because diverse integration is possible, consisting of a plasmonic part and a catalytic part. Herein, we demonstrated ethanol dehydrogenation under light irradiation using Ag-Ni binary nanoparticles with different shapes, snowman and core-shell, as plasmonic catalysts. The surface plasmon formed in the Ag part enhanced the surface catalytic reaction that occurred at the Ni part, and the shape of the nanoparticles affected the extent of the enhancement. The surface plasmon compensated the thermal energy required to trigger the catalytic reaction. The absorbed light energy was transferred to the catalytic part by the surface plasmon through the nonradiative hot electrons. The effective energy barrier was greatly reduced from 41.6 kJ/mol for the Ni catalyst to 25.5 kJ/mol for the core-shell nanoparticles and 22.3 kJ/mol for the snowman-shaped nanoparticles. These findings can be helpful in designing effective plasmonic catalysts for other thermally driven surface reactions.