Ultraviolet and infrared excitable inorganic-organic hybrid materials: Synthesis, characterization and anti-counterfeiting applications

Luminescence materials have received extensive attention for anti-counterfeiting applications due to their low-cost fabrication and simple verification advantages. However, single-emitting encryption can be easily cracked. Therefore, the development of multi-responsive anti-counterfeiting strategies is urgent. Here, we report a facile and universal method to fabricate ultraviolet and infrared excitable inorganic-organic hybrid materials that consist of up-conversion nanoparticles (UCNPs) and organic afterglow materials. With this method, UCNPs can be assembled onto organic afterglow materials driven by the electrostatic interactions between the two components. As a proof-of-concept, a NaYF 4 : Yb, Er UCNPs@catechol-doped cyanuric acid (cd-CA) composite was designed and served as a secret anti-counterfeiting ink material. The security label using the hybrid material as an information carrier shows multiple encryption signals, such as fluorescence, up-conversion, phosphorescence, and infrared thermal imaging, increasing security.