ABSTRACT: Colloidal nanocrystals are synthesized from a wide range of inorganic and organic materials, with a wide range of sizes and shapes. Usually they offer size tunable physical and optical properties due their large surface to volume ratios and due to quantum confinement effects. This flexibility in controlling their properties combined with their simple solution processing makes them promising for many applications, in fields ranging from opto-electronics to biomedicine. Nevertheless, there is basically only one application, where the colloidal nanocrystals are implemented in a commercial device, which is light conversion, nowadays integrated into quantum dot TV-sets and eventually in LED-lightening devices. Thus, there is still the questions to be answered what for colloidal nanocrystals are useful. I will report several attempts to apply colloidal nanocrystals in novel fields of application including mid-infrared detection, photocatalytic generation of H2O2, X-ray detection, and photoexcitation of single cells. The materials synthesized for these purposes include PbS nanocrystals with unusual large dimensions, hydrophobic nanocrystals from organic pigments, perovskite nanocrystals, as well as hierarchical nano-architectures with bio-inspired shapes. Their syntheses will be discusses together with their basic properties, and their potential use will be described.
BIOGRAPHY: Wolfgang Heiss studied physics at the University of Innsbruck, in Austria and received a PhD from the Vienna University of Technology. After a short Post Doc period, during which he worked also as a guest in the UK user station of the Free Electron Laser Facility FELIX in the Netherlands, he obtained an assistant position at the Johannes Kepler University Linz, in Austria. There, he made his habilitation in experimental physics. While in all this years between 1992 and 2002 the research topics were exclusively grouped on classical solid state physics and on crystalline and epitaxial semiconductors, after the habilitation the experimental work shifted continuously to colloidal nanocrystal materials. Due to achievements on colloidal materials, Wolfgang Heiss obtained a position for Solution Processes Semiconductor Materials in 2014 at the Friedrich Alexander University Erlangen Nürnberg, in Germany. Even though the home institute, which is called Materials for Electronics and Energy Technology, is located on the University Campus in Erlangen, Wolfgang Heiss works with his group at a place which is called Energy Campus Nürnberg, which was founded by the state of Bavaria to solve the recent and upcoming energy related problems of this specific area.