Characterization of the shape of gold nanoparticles prepared by thermal annealing

Gold nanoparticles - which are intended to be used as transducers in a localized surface plasmon resonance (LSPR) sensor - were prepared by thermally annealing various layers of gold thin films deposited on glass substrate. The size and distribution of nanoparticles were investigated by atomic force microscopy (AFM). The changes in the nanoparticle shape in function of the deposition and annealing parameters are characterized. A novel parameter called localization factor was used to investigate the shape of the resulting particles. A common problem concerning the AFM imaging of nanoparticles, namely the tip convolution effect was studied, and possibilities to use the localization factor parameter to optimize surface reconstruction algorithms via tip deconvolution is demonstrated.