Abstract

Micron and sub-micron particles tend to be self-organized into well-defined arrays stimulated by solvent evaporation, while this processing does not work for assembling the nanoparticles, especially for the creation of monolayered pattern. Its intrinsic difficulty is mainly related to the evaporations and convections occurred at much larger volume than nanoparticle size, so that multilayered nanoparticle arrays are usually created. In this paper, we report that solvent evaporation and nanoparticle convection are artificially confined in nanoscale spaces nearby solid-liquid-gas interfaces, gold nanoparticle strip with a width of 1 micron are generated by optimizing the contact angle. The arrays with interparticle gaps smaller than 3 nm are hexagonally stacked in three-phase interfaces. Variable numbers of stacked layers and clean surfaces of the assembled nanoparticles are obtained by optimizing experimental parameters. The SERS properties of the assembled nanoparticle arrays rely on their stacking number and surface roughness of gold nanoparticles.

© 2013 Optical Society of America