Analysis of Localized Surface Plasmon Resonance in Glass-supported Gold Nanoparticles with a Hexagonal Pattern

An approach has been devised to create a hexagonal pattern of glass-supported gold nanoparticles (AuNPs) with controllable particle size and inter-particle spacing, by combining the self-assembly of block copolymer micelle-loaded metal precursors with a seeding growth method. Absorbance spectra as an optical response of the AuNP arrays were measured to obtain their LSPR peak position (lambda(LSPR)). There was a red shift in lambda(LSPR) with increasing cover medium refractive index for all fabricated and simulated arrays. A comparison between computed and measured lambda(LSPR) for a 33 nm AuNP array suggests that large nanoparticles produced by this fabrication method have ellipsoidal shapes rather than spherical ones, as in the case of small AuNP arrays.