Abstract
In this dissertation, we regard the gold nanoparticles as “artificial atoms＂to arrange the gold nanoparticle superlattices and tune the lattice constants for polasmonic properties. Therefore, via capillary force, we can use the thiolated gold nanoparticles to form the close packed gold nanoparticle superlattices. Moreover, via the different chain lengths of alkanethiols (C12-C18), the lattice constants can be controlled. Among different gold nanoparticle superlattices, the interparticle gaps are precisely controlled form 3.4 nm to 2.3 nm. The 1.1 nm variation results in the shift of the surface plasmon resonance from 575 nm to 607 nm (with 32 nm red shift) and experimentally confirms the near filed coupling effect. However, it is difficult to massively control gold nanoparticles, thus, in the past few years, we have developed several kinds of approaches for patterned controlling nanoparticles: One of them is Microcontact Electrochemical Conversion approach. Applied bias between stamp and sample and via electrochemical conversion, the pattern of stamp can transfer to the sample, which was preassembled on self-assembled monolayers. This approach provides a high resolution patterns ~300 nm and functional range can exceed to hundreds of micrometers. Afterward, via electrostatic force, colloidal gold nanoparticles can absorb on the patterned SAMs to form patterned nanoparticle configuration. The other approach takes advantage of vacuum ultraviolent lithography to fabricate hdrophilic/hydrophobic SAM patterns. Via capillary force, the silica microspheres can patternedly arranged on substrate with close packed configuration. In addition, we also study physical characteristics of gold colloid and SAMs, especially for APTMS. With terminated group of NH3+, APTMS monolayer is investigated by Kevin force microscopy with a surface potential ~130 eV of positive charges. On the other hand, the colloidal gold nanoparticles are confirmed with negative charges by photoelectron spectrum measurement.