Synthesis Of Functional Silicon-Based Nanomaterials Inks For Anti-counterfeiting Applications

As a major global challenge,counterfeiting products pervade every field of modern society.Traditional anti-counterfeiting inks and encryption technologies are easily copied due to their single anti-counterfeiting mode and predictable coding mechanism.The physical unclonable function(PUF)has emerged as an important pathway for estabilishing high-security anti-counterfeiting,due to its multi-level encryption and uncertain encoding method.Taking advantages of machine algorithm and artificial intelligence(AI)recognition,anti-counterfeiting tags with surface-enhanced Raman scattering(SERS)and fluorescence properties have been explored for high-level anti-counterfeiting applications.In recent years,one-dimensional silicon-based nanomaterials featuring excellent optical properties have become promising candidates for the preparation of high-performance nanoinks.Herein,we intend to construct functional silicon-based nanomaterials inks with fluorescence and SERS properties,suitable for multi-mode PUF anti-counterfeiting applications through high-encoding capacity algorithms and AI schemes.The main research strategies and results are as follows:Chapter 1:We first summarize the development and applications of anti-counterfeiting materials.Then,we review the progresses of anti-counterfeiting applications of functional silicon-based nanomaterials inks.Finally,we discuss the feasibility of high-encoding capacity algorithm and artificial intelligence for anti-counterfeiting application.Chapter 2:The one-dimensional fluorescent silicon nanorods(SiNRs)functionalized with 4-mercaptobenzoic acid(SH-SiNRs)are prepared by microwave radiation,and then decorated with Au nanoparticles and dyes(such as rhodamine B(RB),rhodamine 6G(R6G)and fluorescein isothiocyanate(FITC)).The as-prepared functional silicon-based nanomaterials inks(Au-SH-SiNRs)exhibit fluorescence and SERS properties.In macroscopic level,the multi-color fluorescent security tags allow frequent and fast authentication by the smart phone or naked eyes.Moreover,upon the solvent evaporation,the disordered distribution of nanoinks at the micro-or nano-scale and the randomness of the domains make the optical signals impossible to forge.In microcosmic level,distribution of nanoinks can be read by confocal Raman system with different magnifications.Of particular significance,the stochastic points at low magnification(l0×)can endow the tags with a huge encoding capacity of over 6.43 ×1024082 through machine learning algorithms.Moreover,the physical unclonable shapes of Raman images at high magnification(100×)can be recognized by AI recognition strategy with 98%accuracy.Chapter 3:We combine the above-mentioned functional silicon-based nanomaterials inks and photodegradable polymer film to fabricate dynamic anti-counterfeiting tags.The three-dimensional(3D)microscopic anti-counterfeiting tags with ultraviolet radiation-response property can be used for dynamic anti-counterfeiting.In addition,dual AI recognition technology is carried out for dynamic 3D SERS anti-counterfeiting(recognition accuracy at high magnification:～90%).In summary,taking advantages of the unique opticle properties of silicon-based nanomaterials inks,we achieve the multi-level,fast and dynamic anti-counterfeiting through high-encoding capacity algorithms and AI recognition technology.The above research is helpful for promoting the application of functional silicon-based nanomaterials inks in widespread anti-counterfeiting applications.