Water-based assembly and purification of plasmon-coupled gold nanoparticle dimers and trimers

Abstract

We describe a simple one-pot water-based scheme to produce gold nanoparticle groupings with short interparticle spacings. This approach combines a cross-linking molecule and a hydrophilic passivation layer to control the level of induced aggregation. Suspensions of dimers and trimers are readily obtained using a single electrophoretic purification step. The final interparticle spacings allow efficient coupling of the particle plasmon modes as verified in extinction spectroscopy. Copyright © 2012 Sébastien Bidault and Albert Polman.