Journal of the American Chemical Society, Vol.130, No.3, 824-824, 2008
Tunable plasmonic response from alkanethiolate-stabilized gold nanoparticle superlattices: Evidence of near-field coupling
We report on the self-assembly of large-area, highly ordered 2D superlattices of alkanethiolate-stabilized gold nanoparticles (-10.5 nm in core diameter) onto quartz substrates with varying lattice constants, which can be controlled by the alkyl chain lengths, ranging from C12 (1-dodecanathiolate), C14 (1-tetradecanethiolate), C16 (1-hexadecanethiolate), to C18 (1-octadecanothiolate). These 2D nanoparticle superlattices exhibit strong collective surface plasmon resonance that is tunable via the near-field coupling of adjacent nanoparticles. The approach presented here provides a unique and viable means of building artificial 'plasmonic crystals' with precisely designed optical properties, which can be useful for the emerging fields of plasmonics, such as subwavelength integrated optics.