Abstract: A method for surface modification of nanoparticles includes the separate steps of removing ligands from the surface of the nanoparticles to form ligand-free nanoparticles, and mixing new ligands with the ligand-free nanoparticles to form modified nanoparticles.

Abstract: A method of preparing a mechanoluminescent material includes the steps of: a) providing a mixture including precursors of a base material, a fluxing agent, and at least one lanthanide ion; b) heat-treating the mixture to obtain the mechanoluminescent material; and c) optionally grinding the mechanoluminescent material into powder form; wherein the fluxing agent facilitates incorporation of the at least one lanthanide ion into the base material. A composite material includes a first mechanoluminescent material, wherein the first mechanoluminescent material includes at least 2-3 mol % of a lanthanide ion.

Abstract: Systems and methods which provide anti-counterfeiting patterns tagged with multi-mode nanotaggants, such as may comprise single-mode nanoparticles, multi-mode nanoparticles, or a combination thereof, are described. The multi-mode nanotaggants of embodiments are configured to exhibit prescribed emissions by excitation at distinct stimulus wavelengths. Decryption of anti-counterfeiting patterns tagged with multi-mode nanotaggants of embodiments of the invention may be achieved by examining temporal color responses of the pattern to varying illuminations. In addition to the various color codes that may be encrypted into an anti-counterfeiting pattern using nanotaggants, embodiments provide various graphic codes that may be encrypted into anti-counterfeiting patterns. Such graphic codes may not only comprise the graphic pattern of the anti-counterfeiting pattern itself, but one or more graphic patterns of nanotaggants of the anti-counterfeiting pattern.

Abstract: A method for surface modification of nanoparticles includes the separate steps of removing ligands from the surface of the nanoparticles to form ligand-free nanoparticles, and mixing new ligands with the ligand-free nanoparticles to form modified nanoparticles.

Abstract: Systems and methods which provide anti-counterfeiting patterns tagged with multi-mode nanotaggants, such as may comprise single-mode nanoparticles, multi-mode nanoparticles, or a combination thereof, are described. The multi-mode nanotaggants of embodiments are configured to exhibit prescribed emissions by excitation at distinct stimulus wavelengths. Decryption of anti-counterfeiting patterns tagged with multi-mode nanotaggants of embodiments of the invention may be achieved by examining temporal color responses of the pattern to varying illuminations. In addition to the various color codes that may be encrypted into an anti-counterfeiting pattern using nanotaggants, embodiments provide various graphic codes that may be encrypted into anti-counterfeiting patterns. Such graphic codes may not only comprise the graphic pattern of the anti-counterfeiting pattern itself, but one or more graphic patterns of nanotaggants of the anti-counterfeiting pattern.