Self-Assembly Guided One-Dimensional Arrangement of Gold Nanoparticles: A Facile Approach

Abstract

Gold nanoparticles (AuNPs) reveal fascinating electronic and optical properties, when they organize into one-dimensional architectures. Here, we developed a simple approach to immobilize the AuNPs in a well-aligned one-dimensional arrangement on a silicon surface. A conformationally ordered hexadecyl (HD) monolayer attached to a silicon substrate through Si−C covalent linkage was used as a chemical template to construct the nanopattern in a linear fashion by intermittent-contact mode scanning probe anodization. A positive bias voltage was applied to the silicon substrate at 10% relative humidity and constructs the highly reproducible <30 nm wide SiO2 pattern. The site selective assembly of the amino terminated monolayer on the SiO2 pattern guided the anchoring of citrate stabilized AuNPs in linear arrangements with controlled interparticle distance, as determined by electrostatic interactions, whereas the HD-covered surface remained unexposed to the AuNPs.