An all-in-one nanoprinting approach for the synthesis of a nanofilm library for unclonable anti-counterfeiting applications

In addition to causing trillion-dollar economic losses every year, counterfeiting threatens human health, social equity and national security. Current materials for anti-counterfeiting labelling typically contain toxic inorganic quantum dots and the techniques to produce unclonable patterns require tedious fabrication or complex readout methods. Here we present a nanoprinting-assisted flash synthesis approach that generates fluorescent nanofilms with physical unclonable function micropatterns in milliseconds. This all-in-one approach yields quenching-resistant carbon dots in solid films, directly from simple monosaccharides. Moreover, we establish a nanofilm library comprising 1,920 experiments, offering conditions for various optical properties and microstructures. We produce 100 individual physical unclonable function patterns exhibiting near-ideal bit uniformity (0.492 +/- 0.018), high uniqueness (0.498 +/- 0.021) and excellent reliability (>93%). These unclonable patterns can be quickly and independently read out by fluorescence and topography scanning, greatly improving their security. An open-source deep-learning model guarantees precise authentication, even if patterns are challenged with different resolutions or devices. A laser printing approach generates physical unclonable fluorescent patterns, made from simple sugar. These environmentally friendly and ultraviolet-stable materials can be applied as anti-counterfeiting labels.

Automated summary

Counterfeiting not only causes trillion-dollar economic losses annually, but also threatens human health, social equity, and national security. Researchers have developed a nanoprinting-assisted flash synthesis approach to create fluorescent nanofilms with physical unclonable function micropatterns in milliseconds. These unclonable patterns can be quickly and independently read out by fluorescence and topography scanning, greatly enhancing their security.