Chemosensitive Thin Films Active to Ammonia Vapours
Agnieszka Brochocka1, Aleksandra Nowak1, Hanna Zajączkowska1
1Department of Personal Protective Equipment, Central Institute for Labour Protection-National Research Institute, 90-133 Lodz, Poland.
Sensors (Basel, Switzerland)
|April 30, 2021
Summary
Researchers developed new sensors for detecting toxic ammonia gas. The most effective sensor used reduced graphene oxide (rGO) in a polycarbonate matrix, showing a significant 14.21% resistance change to ammonia vapors.
Area of Science:
- Materials Science
- Chemical Sensing
- Nanotechnology
Background:
- Ammonia is a toxic gas requiring sensitive detection methods.
- Developing advanced materials for gas sensing is crucial for environmental and safety monitoring.
- Carbon-based nanomaterials offer unique electrical properties for sensor applications.
Purpose of the Study:
- To develop and evaluate novel dispersive systems for ammonia gas sensing.
- To investigate the performance of different nanomaterials (MWCNs, rGO, polyaniline) within a polymer matrix.
- To compare the efficacy of spraying and drop-casting deposition methods for sensor fabrication.
Main Methods:
- Preparation of polymer dispersions using polycarbonate, methylene chloride, MWCNs, rGO, and polyaniline.
- Fabrication of chemosensitive films on comb electrode substrates via spraying and drop-casting.
- Electrical characterization of sensor responses to varying concentrations of ammonia vapor.
Main Results:
- Multiple dispersive systems were tested for ammonia sensitivity.
- The sensor utilizing reduced graphene oxide (rGO) deposited by drop-casting exhibited the highest response.
- A maximum resistance change of 14.21% was recorded for the optimal rGO-based sensor.
Conclusions:
- Dispersive systems incorporating nanomaterials show promise for ammonia detection.
- Drop-casting is an effective method for fabricating high-performance ammonia sensors.
- Reduced graphene oxide is a highly suitable material for sensitive and responsive ammonia gas sensors.
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