Cesium Lead Bromide Nanocrystals: Synthesis, Modification, and Application to O₂ Sensing

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Inorganic perovskite nanocrystals (NCs), specifically CsPbBr3 (CPB), exhibit fluorescence quenching in the presence of oxygen (O2).
• This property makes CPB NCs potential candidates for optical gas sensing applications.

Purpose of the Study:

• To synthesize CPB NCs with controlled shapes and sizes for optical gas sensing.
• To investigate the impact of NC characteristics and substrate properties on O2 sensor performance.

Main Methods:

• Synthesis of CPB NCs with diverse morphologies and dimensions.
• Fabrication of O2 gas sensors using CPB NCs on various porous and nonporous substrates.
• Evaluation of sensor response based on NC shape, aggregate size, and substrate pore characteristics.

Main Results:

• The highest O2 sensor response was achieved using CPB NCs deposited on a porous substrate.
• Porous substrates facilitated rapid O2 diffusion, leading to effective exposure of the NC surface to the gas.
• Interfacial interactions between NC surfaces and substrates significantly influence sensor performance.

Conclusions:

• Cesium lead bromide perovskite nanocrystals are viable materials for optical oxygen gas sensing.
• Optimizing substrate porosity and understanding interfacial interactions are crucial for developing high-performance gas sensors.