Final Report Summary - LIGHT4FUNCTION (Light-controlled and Light-driven Molecular Action)
In Light4Function, work has been focusing primarily on fundamental research dedicated to design, understand, and optimize photoswitchable molecules. For example, the light-induced switching process could be rendered much more efficient and reliable, giving rise to very robust switches that could be used in optoelectronic devices that require many switching operations without failure. Furthermore, various approaches to operate photoswitches using visible light instead of harmful UV-light have been developed. These molecules are important in the context of emerging light-induced therapies since red light can more deeply penetrate into tissue. Beyond investigating photoswitches and unravelling the underlying relationship between their chemical structure and light-induced switching behavior, the Light4Function Team has been taking a step further by putting these molecules to use. For example, they could control dynamic chemical connections, in other words the process of bond-making and bond-breaking, using light. Using this approach, they were able to create polymeric materials that allow for damage healing as well as reversible gluing simply by exposure to (sun)light. Furthermore, they could develop smart yet low-cost sensors, which upon exposure to UV light, for example in the sun, can be activated and detect biogenic amines, related to spoilage of food. In addition to controlling chemistry with light, the team (in collaboration with another ERC team at the University of Strasbourg) could integrate their photoswitches into organic thin film transistors and fabricate flexible and light-weight optical memories with high storage density, low volatility (little data loss over time), and fast response. Last but not least, together with colleagues from the Technical University Eindhoven in the Netherlands some of their photoswitchable molecules were incorporated into a special plastic film, in which they are nicely aligned and thus work in concert. When exposed to sunlight these films start to bend up and down and this oscillatory motion could be used to propel dust from a surface, thereby providing self-cleaning coatings, for example for windows or solar cells. With these major advances during the Light4Function Project and many more ideas in mind the team is convinced that photoswitchable molecular systems will enable a major innovation push and future breakthroughs in material and device technologies.