Ammonia Gas Sensor Fabricated by Multifunctional ZnO/GO Nanocomposites for Long-Term, Self-Powered Monitoring

Area of Science:

• Materials Science
• Environmental Science
• Energy Storage

Background:

• Ammonia (NH3) is a key atmospheric gas impacting environmental quality and a promising hydrogen carrier.
• Developing sensitive, stable, and self-powered NH3 sensors is crucial for environmental monitoring and safety.
• Simultaneous applications of materials for sensing and energy storage are desirable for integrated systems.

Purpose of the Study:

• To synthesize a novel zinc oxide/graphene oxide (ZnO/GO) nanocomposite.
• To evaluate its performance as an ammonia (NH3) gas sensor with high sensitivity and stability.
• To assess its potential as an electrode material for supercapacitors and its integration with a self-powered system.

Main Methods:

• One-step in situ polymerization to synthesize ZnO/GO nanocomposites.
• Fabrication of gas-sensitive films and supercapacitor electrodes.
• Testing of ammonia sensor performance (detection limit, response/recovery time, stability).
• Development of a wearable triboelectric nanogenerator (TENG) for self-powered sensing.

Main Results:

• Achieved a specific capacitance of 131 F/g at 1 A/g for supercapacitors.
• Demonstrated a low NH3 detection limit of 0.1 ppm with fast response (17 s) and recovery (26 s) at 10 ppm.
• Exhibited excellent long-term stability with <1% relative standard deviation over 210 days.
• Successfully powered the NH3 sensor using a wearable TENG generating 4.1 mW.

Conclusions:

• The ZnO/GO nanocomposite shows dual functionality for high-performance ammonia sensing and supercapacitor applications.
• The developed self-powered sensing system offers enhanced spatial coverage and operational flexibility for NH3 monitoring.
• This integrated approach holds significant promise for real-time environmental and industrial safety applications.