Luminomagnetic Afterglow Assimilated Multi-Mode Protection with Inventive Golden Security Ink for Anticounterfeiting Applications

The designing of luminescent multifunctional materials with an improvised multistage excitability and data storage capacity for advanced anticounterfeiting technology is still challenging. Lanthanide-based nanomaterials are more often used due to their ample intermediate energy states and distinct spectroscopic profiles. But still the earlier existing anticounterfeiting technologies based on lanthanide nanomaterials have a limited complexity and capability to encrypt important information to protect against counterfeiting. Herein, a novel strategy is being contrived for the development of dual excitable and triple emissive multifunctional security pigment which emit triple wavelengths when excited with two different wavelengths and also have integrated afterglow feature when the excitation source is put off along with the data encryption capability. The respective security pigment is formulated by using the unique combinatory phenomenon of fluorescence-phosphorescence-magnetic features in a single entity. The pigments NaGdF₄:Eu³⁺, SrAl₂O₄:Eu²⁺/Dy³⁺, and NaGdF₄:Yb³⁺/Tm³⁺ provide intense reddish orange, green afterglow, and blue emission at wavelengths 609, 528, and 474 nm (RGB), respectively, when irradiated under a 254 nm UV lamp, when the 254 nm UV lamp was put off, and when irradiated under a 980 nm laser, respectively, and Fe₃O₄ magnetic nanoparticles contributes the magnetic property. The results demonstrate that even under the most rigorous conditions, the outcomes remain stable. Hence, the outstanding results ascertain that the multi-emissive anticounterfeiting along with afterglow feature and information encryption with facile decryption and authentication using luminomagnetic golden security ink could be practically applicable by selecting different excitation modes to enhance the strong security features.