Dual-Mode Afterglow of Organic-Inorganic Hybrid Metal Halides for Multi-Dimensional Information Encryption

Area of Science:

• Materials Science
• Optoelectronics
• Chemistry

Background:

• Organic and hybrid materials with room-temperature phosphorescence (RTP) and long persistent luminescence (LPL) are crucial for time-resolved optoelectronic applications.
• Achieving distinct RTP and LPL within a single material is challenging but essential for applications like multilevel optical encryption.

Purpose of the Study:

• To develop a single material system capable of exhibiting intrinsically distinct room-temperature phosphorescence (RTP) and long persistent luminescence (LPL).
• To explore the potential of such a material for advanced applications, specifically in multilevel optical encryption.

Main Methods:

• Synthesis of a Mn²⁺-doped organic-inorganic hybrid metal halide.
• Characterization of luminescence properties under UV excitation (RTP) and X-ray irradiation (LPL).
• Analysis of recombination pathways responsible for the distinct emission behaviors.

Main Results:

• The synthesized material displays bright yellow RTP under UV light and a red LPL lasting over 600 seconds under X-ray irradiation.
• Distinct emission mechanisms were identified: RTP originates from triplet excitons in the organic ligand, while LPL is Mn²⁺-centered, driven by trapped charge carriers.
• The material demonstrates excitation-dependent luminescence, allowing for temporal and spectral control of optical signals.

Conclusions:

• A pathway-engineered strategy successfully created a multi-mode phosphorescent material with distinct RTP and LPL.
• This material enables a multidimensional optical encryption platform based on time-space-energy encoding.
• The findings pave the way for designing advanced materials for intelligent optoelectronic devices.