Surface chemistry is the study of chemical reactions and processes at surfaces. In the MCAG we are interested in studying a range of materials with different surfaces, including high surface area objects such as nanoparticles, nanowires and nanoporous solids. The high surface areas of nanomaterials means that their chemical and physical properties are dominated by their surface atoms, rather than their bulk atoms, which can be readily manipulated for specific applications. For example, light emission from semiconductor nanoparticles often changes with decreasing diameter.
Figure 1: Surface Chemistry
Within the MCAG we use chemistry to change the surfaces and properties of various materials for a range of applications, including nanowires for sensing, doped semiconductor substrates for microelectronics and metallic thin films for energy applications. Such treatments often involve coating surfaces with densely packed layers of self-assembled monolayers (SAMs) of organic molecules, e.g. thiols readily form SAMs on Au surfaces. Currently in the MCAG we are using SAMs of organic molecules to control doping levels in semiconductors such as Si, Ge and GaAs, for microelectronic applications, as well as creating metal alloy nanoparticles from metallic thin films for clean energy fuel cells.