Plasmonic Photoelectrocatalysis in Copper-Platinum Core-Shell Nanoparticle Lattices

This paper reports that strongly coupled bimetallic core-shell nanoparticle arrays show photoelectrocatalytic activity for hydrogen evolution reactions (HER). We fabricated large-area Cu-Pt nanoparticle lattices by combining top-down lithography and solution-based chemistry. These coupled lattices support two different types of plasmon modes, localized surface plasmons from individual particles and surface lattice resonances (SLRs) from the 2D lattice, that increased HER catalytic activity under white-light illumination up to 60%. Comparing photoelectrocatalytic performances of the two plasmon modes at different wavelength ranges, we found that SLRs had two-fold activity enhancement over that from localized surface plasmons.