Thin films of metal oxide nano-particles (NPs) are used in nano-technological applications, such as semiconductors and solar cells, as these films can potentially give the desired optical and electrical properties. Films of NPs with a controlled packing can be made by forming Langmuir films of NPs at an air-aqueous interface and then by depositing and sintering these films to a substrate. However, Langmuir films of metal oxide NPs (SiO2 or TiO2) cannot form at air-water interfaces, as their high hydrophilicity makes them instable at the air-water interface. A common method to overcome this problem is to hydrophobically modify the NPs by using surfactants or polymers. In this talk, we will discuss an alternate way of making non-modified metal oxide NPs stable at air-aqueous interfaces, which involves the addition of inorganic salts to the aqueous phase. We will also discuss how to modify the physical properties (roughness and surface charge) of the transferred films by mixing NPs of different sizes and types at the air-aqueous interface.
Presenter:
Cathy McNamee obtained her D.Sc. from Kyoto University (Japan) in 2001. She then made post-doctoral research at Ulm University (Germany), Lund University (Sweden), Kyoto University (Japan), and the Max Planck Institute for Polymer Research (Germany). Cathy McNamee joined Shinshu University (Japan) in 2008, where she became a full professor in 2021.
