Multimode Stimulus-Responsive Room Temperature Phosphorescence Achieved by Doping in 0D Hybrid Zinc Halides for Dynamic Anticounterfeiting

Abstract

Zero-dimensional hybrid metal halides (0D HMHs) are attractive candidates for room-temperature phosphorescence (RTP). However, most existing 0D HMHs emit a single color, making it challenging to achieve multicolor luminescence and multistimuli responsiveness while preserving persistent afterglow. In this work, we prepared the 0D hybrid zinc halide material [i-PrTPP]2ZnBr4. Benefiting from hydrogen-bond networks and the heavy atom effect, this material delivered long-lived cyan RTP. Its phosphorescence lifetime reaches 414.92 ms, and the photoluminescence quantum yield (PLQY) is 22.12%. We further doped the host with Sb3+ and Mn2+. The doped samples emit red fluorescence (PLQY = 51.92%) and green fluorescence (PLQY = 93.57%) separately, while the original cyan phosphorescence is retained. The Mn2+-doped material also shows an unusual mechanoluminescence (ML). Increasing the dopant concentration enhances the energy-transfer efficiency from the organic triplet (T1) state to the dopant ions, thereby enabling temporal modulation of the luminescence. Combining dual-mode emission, ML, and temporal regulation, these materials can be used for dynamic optical encoding and information encryption. This study offers a new route to develop multiresponsive luminescent materials and advanced dynamic anticounterfeiting techniques.