This paper provides a convenient method for fabricating architectures of Au nanoparticles on solid substrate, with precise position and density control. Our strategy is to modify Au substrate with self-assembled monolayers (SAMs) terminated with different functional groups. They were chosen to be -CH3/-NH2 or -CH3/-SH according to their affinities to Au nanoparticle. Au nanoparticles assemble selectively on -NH2 or -SH terminated locations, the -NH2 functional group binding electrostatically to the nanoparticles whereas the -SH groups bonding chemically. The SAMs, acting as guiding templates for Au nanoparticles, were fabricated by the microcontact printing (μCP) technique. A patterned or unpatterned SAM was prepared by using patterned or unpatterned poly(dimethyl)siloxane (PDMS) stamp, respectively. The coverage of -CH3 terminated SAM in the contact region is controlled by changing the concentration of `ink' solution for the stamp. After immersing the printed SAM into -SH or -NH2 thiol solutions for 2 h, a mixed SAM with a predetermined coverage of -SH or -NH2 was formed in the contact regions, and a pure -SH or -NH2 SAM was formed in the intervening area. The position and density of nanoparticles on the surface were determined by the distribution of the underlying functional groups.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Surfaces and Interfaces