Bio-Inspired Multicolor and Red Afterglow LiNbO3 Phosphors for Environment-Interactive Anti-Counterfeiting and Ratiometric Thermometry

Inspired by the natural responsive phenomena, a single-host, dual-stimuli-responsive luminescent system based on LiNbO 3 :Pr 3+ /Dy 3+ was developed via a conventional high-temperature solid-state method. The co-doped phosphors showed yellow, orange, and red-light emissions under excitation at 290, 365, and 461 nm, respectively. After cessation of UV excitation, the co-doped phosphor exhibited a red afterglow with a duration of six times longer than that of the Pr 3+ -only sample. Meanwhile, the temperature-dependent luminescence behavior allows high-sensitivity ratiometric optical thermometry, with a maximum relative sensitivity of 2.30% K −1 under 461 nm excitation. By integrating excitation-dependent color tunability, afterglow, and near-infrared emission within a single material platform, this results demonstrates a multimodal luminescent system capable of simultaneous information storage, anti-counterfeiting authentication, and optical sensing, highlighting its potential for high-security and multifunctional applications.