Security Applications of Persistent Luminescence Nanoparticles

Persistence luminescence nanomaterials are innovative materials that have been investigated and explored by several researchers. They have a variety of special characteristics such as long-lasting intense afterglow emission with long persistence time. The most favorable transition in persistence luminescence occurred due to the trap distribution by activating dopant ions and varying host lattices combination, and the developed trap depths were examined by thermoluminescence analysis. Different color dynamics have been attained after numerous excitations in the NIR to UV wavelength range. Dynamic anti-counterfeiting has been attained by adjusting the concentration of doping ions, types of codopants, trap depths, etc. Because these nanoparticles can continue to emit light even after the excitation source has stopped, they are excellent options for a range of security-related applications. The lanthanide and transition metal ions are quite useful in this field. In the area of security and anti-counterfeiting applications, nanomaterials such as downconverting and upconverting materials are most useful. The present chapter provides an overview of the design, synthesis, and structure of novel long-lasting phosphors, as well as their multiple uses, including security, information protection, data encryption, latent fingerprinting, lip printing, and anti-counterfeiting applications. Persistence luminescence nanoparticles have the potential to provide a growing number of complex and efficient solutions for many security issues as long as research and development in this field continue.