Assembly of single-walled carbon nanotubes on patterns of Au nanoparticles

We report on the assembly of single-walled carbon nanotubes (SWNTs) and gold nanoparticles (NPs) hybrid structure without any surface modification of SWNTs on patterns of Au nanoparticles (NPs). Microscale Au NP patterns were created on composite self-assembled monolayer (SAM) templates of octadecanethiol (ODT) and octanedithiol (OD) through self-assembly of Au NPs via the thiol-Au chemical bond onto the OD region. On such templates, we observed extensive adhesion and strong affinity of SWNTs on the Au NPs and no SWNT on ODT. We also examined systematically the adhesion of SWNTs on ODT with varying coverage of vapour-deposited Au. We observed little SWNT attachment even when there are high-density of Au clusters on the ODT SAM. Extensive adhesion of SWNTs is observed only when the coverage of ODT by Au is almost complete. Dynamic contact angle measurements of dichlorobenzene on the ODT/Au substrates revealed a direct correlation between the surface wettability and the SWNT assembly on a molecular template.