Modulation of carbon dots hybrids lasers for high security flexible multi-level anti-counterfeiting

Anti-counterfeiting materials development has been raised for a long time to improve the level of security against counterfeiting. Increasing counterfeiting difficulties as well as reducing difficulties of materials preparation are two major concerns in the development of anti-counterfeiting materials. Herein, carbon dots (CDs) and triethyl 1,3,5-benzenetricarboxylate (Et3BTC), both of which show two random lasing peaks located around 325 nm and 450 nm at 265 nm excitation are chosen as two lasing mediums to form hybrids. Moreover, lasing intensity ratio of the two lasing bands from the hybrids can be tuned by changing the working temperature, excitation area, and even bending angle of substrate. As a result, a strategy of dual random lasing medium modulation based high security flexible multi-level anti-counterfeiting technique is developed. Thus, it is suitable for anti-counterfeiting of high-value items due to its high security and excellent waterproofness. This work will provide a perspective to boost the development of high security anti-counterfeiting techniques.