Patterning of gold nanoparticle rings by manipulation of wetting coverage

• Main Author: Wang, Puqun.
• Other Authors: Wong Chee Cheong
• Format: Final Year Project
• Language: English
• Published: 2012
• Subjects: DRNTU::Engineering::Materials::Nanostructured materials
• Online Access: http://hdl.handle.net/10356/48416
• Institution: Nanyang Technological University

This report presents a simple, large scale and low-cost alternative approach to fabricate gold nanoparticle (Au NP) ring arrays on Si substrate by using hexagonal close packed (HCP) polystyrene (PS) monolayer as a template and manipulating chemical wetting coverage. With no involvement of sophisticated equipment, Au NP ring structures of tunable sizes and wall thickness are generated. In addition, a qualitative threshold model that well describes the profile of effective packing density of templating molecules is established. Within the framework of the model, the geometric parameters of the ring arrays prepared from this pure chemical approach, the effects of wetting order as well as the selection of surface modifying chemicals are discussed. As the proposed approach takes advantage of chemical wetting difference to specifically modify the substrate surface, it is reasonable to conclude that the shape, size and wall thickness of the Au NP ring arrays are tunable by varying the templating objects and the chemicals used for surface modification, implying potential application in sensing and spectroscopy by engineering ring arrays on demand.