Chameleonano

The present popularity of everything that involves ‘nano’ is not just a hype. In case of semiconductor and metal nanoparticles new physical and chemical properties arise from the nanometer dimensions. This results in fascinating size dependent optical and electrical properties: the particles change color, just like chameleons, when the size is tuned in the nanometer regime. This presentation will focus on nanocrystalline semiconductors (also known as quantum dots, QDs) where quantum size effects are responsible for a change in the electronic structure. After an historical introduction, highlighting the role of new colloidal synthesis techniques for semiconductor nanocrystals,  the unique size dependent properties are explained and demonstrated. In the second part some fun phenomena and applications in biomedical imaging and white lights LEDs will be discussed.