Fabrication Of Controllable Patterned Perovskite Film Array And Its Application In Physical Unclonable Function Anti-counterfeiting Labels

In recent years,anti-counterfeiting technology has been widely used in people's lives,but with the development of technology and science,the counterfeiter's imitation ability has also been greatly improved.It is becoming more and more difficult for consumers and inspection departments to identify and test the authenticity of products through traditional anti-counterfeiting labels.The anti-counterfeiting ability of the previous anti-counterfeiting technology is gradually weakened,not only sometimes can not play the role of anti-counterfeiting,even after being cracked,it may become the Amulet of counterfeiters,causing immeasurable losses to enterprises,individuals and even the country.Therefore,it is an inevitable trend to develop more secure and convenient anti-counterfeiting technology.In recent years,the physical unclonable function(PUF)anti-counterfeiting labels have become a research hotspot in this field.Cesium-lead halide perovskite materials have attracted much attention in the field of optoelectronic devices due to their excellent optoelectronic properties,such as long carrier lifetime,high optical absorption coefficient,adjustable band gap and composition,outstanding quantum yield and so on.In recent years,many excellent researchers have applied cesium-lead halide perovskite with excellent photoelectric properties in the emerging field of high-performance anti-counterfeiting labels.In this paper,we will also propose a PUF anti-counterfeiting label based on CsPbBr₃perovskite nanocrystals and the corresponding recognition algorithm.By combining Surface-Tension-Confined Microfluidics technology with laser engraving technology,we can fabricate CsPbBr₃ perovskite nanocrystalline film with clonable profile and un clonable texture on hydrophobic substrate by laser engraving and droplet evaporation self-assembly.A variety of crystal film contour shapes can be used as"specificator"for image recognition.The recognition speed of the algorithm based on this divide-and-conquer strategy is increased by more than 20 times.At the same time,the anti-counterfeiting label simply packaged by PDMS can be effectively used for at least 60days under normal environmental conditions,and has certain light resistance and heat resistance.Combined with its low cost(2.1×10^-4 USD),fast and convenient verification(12.17 seconds),high coding capacity(2.1×10⁶²³)and so on,our anti-counterfeiting label shows excellent overall performance,and has good practical application potential.