“Thermally activated delayed fluorescence” (TADF) materials are promising for a number of applications ranging from imaging and security, to solar cells and light-emitting diodes and the pixels used in flat panel displays. However, most of the TADF materials made so far are based on metal-organic complexes and organic molecules that have lifetimes of only several microseconds or milliseconds. They are unfortunately sensitive to oxygen too. A team of researchers at Jilin University in Changchun, China, has now developed fluorescent carbon dots embedded inside aluminophosphate zeolites that, after being photoexcited, emit visible blue light for periods as long as 0.35 seconds at ambient temperature and atmosphere. This is among the longest recorded lifetimes yet for a carbon dot-based fluorescent material of this class and the result might be an important step forward towards commercializing these materials………
http://nanotechweb.org/cws/article/tech/68900
