SnO₂QDs sensitized ZnFe₂O₄spheres with enhanced acetone sensing performance

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Developing advanced gas sensors is crucial for environmental monitoring and medical diagnostics.
• Metal oxide composites offer tunable properties for selective gas detection.
• Tin dioxide (SnO2) and zinc ferrite (ZnFe2O4) are promising materials for gas sensing applications.

Purpose of the Study:

• To synthesize porous SnO2/ZnFe2O4 (ZFSQ) composites using SnO2 quantum dots (QDs) for improved gas sensing.
• To investigate the effect of SnO2 QD size and content on the sensing properties of ZFSQ composites.
• To evaluate the potential of ZFSQ composites for acetone detection in exhaled breath.

Main Methods:

• Synthesis of porous ZFSQ composites via an immersion process followed by calcination.
• Characterization of the composite structure and morphology.
• Gas sensing performance evaluation for acetone at various concentrations and temperatures.

Main Results:

• Porous ZFSQ composites exhibited significantly enhanced acetone sensing response compared to bare materials.
• The ZFSQ composite with 5 wt% SnO2 QDs (ZFSQ-5) showed optimal performance.
• ZFSQ-5 achieved a high response of 110-100 ppm to acetone with a low detection limit of 0.3 ppm at 240 °C.
• The quantum dot size effect, heterojunctions, and porous structure contributed to the improved sensing.

Conclusions:

• Porous SnO2 QDs/ZnFe2O4 composites offer a promising platform for high-performance acetone gas sensors.
• The size of SnO2 QDs plays a critical role in enhancing gas sensing capabilities.
• The developed ZFSQ-5 sensor shows potential for non-invasive acetone monitoring in exhaled breath analysis.