Dynamic Fluorescence and Multi-Modal Anti-Counterfeiting Applications in Pb²⁺, Mn²⁺ Co-Doped CsCdCl₃ Perovskite.

Area of Science:

• Materials Science
• Solid-State Chemistry
• Optoelectronics

Background:

• Single-component multimodal luminescent materials are crucial for high-end information encryption.
• Achieving dynamic fluorescence in halide perovskites presents a significant challenge.
• Existing materials often lack the multimodal optical responses required for advanced security applications.

Purpose of the Study:

• To develop a single-component halide perovskite with multimodal luminescence and dynamic fluorescence properties.
• To explore its potential for high-security information encryption.
• To investigate novel optical responses including dynamic fluorescence switching and dual-mode encoding.

Main Methods:

• Co-doping CsCdCl3 perovskites with Pb2+ and Mn2+ ions.
• Investigating optical responses under UV irradiation and varying doping concentrations.
• Analyzing fluorescence switching mechanisms via trap-mediated energy transfer.
• Developing time-dependent dynamic fluorescence encoding strategies.

Main Results:

• Successfully achieved multimodal optical responses including crystal coloration, dynamic fluorescence switching, thermochromism, and long afterglow in CsCdCl3 perovskites.
• Demonstrated reversible fluorescence switching from orange to blue, tunable by UV irradiation power.
• Enabled dual-mode encoding in bright and dark fields with controllable coloration and rapid erasure.
• Developed a time-dependent dynamic fluorescence encoding strategy for advanced encryption.

Conclusions:

• The Pb2+/Mn2+ co-doping strategy effectively creates multimodal luminescent CsCdCl3 perovskites.
• This material offers a novel platform for high-security encryption with dynamic fluorescence and dual-mode storage.
• The findings pave the way for next-generation information security materials with tunable optical properties.