Blue-Light-Excitable Red-Emitting Organic Antimony Halides as a Reversible Humidity Sensor.

Area of Science:

• Materials Science
• Inorganic Chemistry
• Solid-State Physics

Background:

• Zero-dimensional (0D) organic antimony halides are gaining attention for their diverse structures and optical characteristics.
• These compounds offer tunable optical properties and high luminescence efficiency, making them promising for optoelectronic applications.

Purpose of the Study:

• To synthesize and characterize novel 0D organic antimony bromide hybrid structures.
• To investigate the optical properties, specifically luminescence, of these new materials.
• To explore the potential application of these materials in humidity sensing.

Main Methods:

• Synthesis of antimony bromide hybrid structures with specific geometries ([SbBr4] seesaw and [SbBr5] pyramidal).
• Characterization of structural and optical properties, including band gaps and photoluminescence.
• Evaluation of photoluminescence sensitivity to varying relative humidity levels.

Main Results:

• Successful synthesis of new 0D organic antimony bromide structures with seesaw and pyramidal geometries.
• Observation of low band gaps and blue-light excited red emissions attributed to self-trapped excitons.
• Demonstration of a reversible, positive correlation between photoluminescence and relative humidity (30-90%).

Conclusions:

• The synthesized antimony bromide compounds exhibit unique structural and luminescent properties.
• Self-trapped excitons are responsible for the observed broadband emission and large Stokes shift.
• The humidity-sensitive photoluminescence suggests their potential as effective real-time humidity sensors.