Sequential and Reversible Phase Transformations in Zero-Dimensional Organic-Inorganic Hybrid Sb-based Halides towards...

Area of Science:

• Materials Science
• Solid-State Chemistry
• Photochemistry

Background:

• Zero-dimensional (0D) metal halides are recognized for their structure-dependent photoluminescence (PL).
• Organic-inorganic hybrid materials offer tunable optoelectronic properties.
• Antimony (Sb)-based halides are emerging as promising luminescent materials.

Purpose of the Study:

• To synthesize and characterize novel 0D organic-inorganic hybrid Sb-based halides.
• To investigate the relationship between structural phase transformations and photoluminescence properties.
• To explore potential applications in optical fields, such as anti-counterfeiting.

Main Methods:

• Crystallization of two new 0D Sb-based halides: (MTP)₆ SbBr₆ Sb₂ Br₉ ⋅H₂ O (crystal 1) and (MTP)₂ SbBr₅ (crystal 2).
• Induction of a glassy state (glass 3) via heat treatment of crystal 2.
• Triggering reversible phase transformations using water and acetonitrile vapor.
• Characterization of photoluminescence (PL) properties, including dehydration/rehydration and thermal effects.

Main Results:

• Discovery of two new 0D Sb-based halides with reversible structural phase transformations.
• Tunable orange and red emissions observed upon dehydration and rehydration.
• Formation of a glassy state with near-infrared luminescence upon heat treatment.
• Stepwise reverse phase transformation from glassy to crystalline states triggered by vapor stimuli.
• Demonstration of an anti-counterfeiting device based on reversible PL switching.

Conclusions:

• Phase structure engineering in 0D metal halides leads to tunable and reversible photoluminescence.
• The reported Sb-based halides exhibit promising potential for advanced optical applications.
• Reversible phase transformations driven by external stimuli offer new avenues for material design.