Application of Fluorescence Quantum Dots Prepared by Inverse Emulsion Method in Anti-Counterfeiting Encryption

A method was reported about synthesizing all inorganic perovskite quantum dots using inverse emulsion method. In an antisolvent formed by mixing water and oil phases, perovskite quantum dots are directly encapsulated in a polymer suspended in it. The tiny hydrophobic particles formed, which are uniformly dispersed in water, can be stably suspended in an aqueous solvent while being encapsulated in a hydrophobic polymer shell layer, and can potentially be used for cryptographic processing of information. The lead halide chalcogenide quantum dot inks, prepared using the inverse emulsion phase method, combine three polymer materials(PMMA, PS, and PVP) with lead halide chalcogenide quantum dots. Three inks exhibit varying optical properties and stability decay rates over time in different solvents. Effective encryption and decryption engineering of information in the time dimension can be achieved by utilizing the time decay of several anti-counterfeiting inks with different materials in different solvents. Finally, the encrypted information on filter paper was successfully designed to securely encrypt and decrypt the information under 365 nm UV lamp irradiation.