Construction and applications of photo-controlled fluorescent switches based on diarylethene modified red emission carbon dots

Carbon dots (CDs) are of interest due to their exceptional photostability and adjustable fluorescence emission properties. Nevertheless, the traditional synthesized CDs mainly emitted blue or green fluorescence and the emission intensity could not be modulated, which brings challenges to the applications of CDs. In this work, two fluorescent switches were constructed by red fluorescent CDs and two diarylethene molecules. Their fluorescence intensity could be reversibly controlled by UV/Vis lights, and the modulation efficiencies of them could reach 94% and 80%, respectively. The fatigue resistance of the two fluorescent switches could be reached 20 and 12 times, respectively. In addition, the two fluorescent switches were successfully applied in anti-counterfeiting and optical storage. This study will demonstrate a novel approach for the construction of fluorescent switches and broaden their applications.