Ln-MOFs Scintillator for Temperature-Dependent and Dual-Excitation-Responsive Photonic Barcodes

The escalating global counterfeiting crisis demands advanced anticounterfeiting technologies beyond static, single-source-excited photonic barcodes, which are vulnerable to replication and lack an ionizing-radiation response. Herein, we propose smart, responsive, scintillator-based photonic barcodes (SRS-PB) as a transformative solution. A series of isostructural lanthanide metal-organic frameworks (Ln-MOFs), denoted as ZJNU-1002-Ln, exhibits tunable luminescent color through precise adjustment of Eu3+/Tb3+ ratio. Two excitation modalities, including both UV light and X-rays, are integrated in a single system, promoting dual-excitation-responsive luminescence. Such Ln-MOFs-based scintillators present linear X-ray-excited luminescence (XEL) response to dose rates, a great light yield (max ∼37,000 photons MeV-1), low dose rate detection limit (min ∼0.2106 μGy s-1), and excellent irradiation stability. The as-recorded photoluminescence and XEL spectra can be converted to high-capacity barcodes according to the predefinition. Furthermore, temperature-dependent spectral modulation dynamically reconfigures these barcodes under dual excitation sources, accompanied by switchable luminescence colors. This dynamic, multilevel encoding mechanism overcomes the replicability of static optical tags and eliminates sole reliance on UV excitation. These SRS-PB labels provide a delicate platform for unclonable information security and advanced anticounterfeiting.