Magnetic Field-Enhanced NO2 Sensing in Co3O4 Microcubes: Insights from Magnetic Structure Evolution
Runjia Xu1, Yinfang Xu1, Yaru Liu1
1School of Physics and Electrical Engineering, Linyi University, Linyi 276000, China.
ACS Sensors
|March 2, 2026
Summary
Magnetic fields boost the sensitivity of cobalt oxide (Co3O4) gas sensors for detecting nitrogen dioxide (NO2) at room temperature. This magnetic field enhancement significantly improves sensor performance for environmental monitoring.
Area of Science:
- Materials Science
- Nanotechnology
- Chemical Sensing
Background:
- Metal oxide semiconductors are widely used in gas sensors.
- Sensitivity and performance of gas sensors are often limited.
- Magnetic fields can influence charge carriers and surface adsorption.
Purpose of the Study:
- To investigate the effect of magnetic fields on gas sensing properties of Co3O4.
- To develop ultrasensitive NO2 gas detection at room temperature.
- To elucidate the mechanism behind magnetic field-enhanced gas sensing.
Main Methods:
- Hydrothermal synthesis of antiferromagnetic mesoporous Co3O4 microcubes.
- Gas sensing measurements for NO2 detection under varying magnetic fields (up to 150.8 mT).
- First-principles calculations and experimental studies to analyze magnetic structure and adsorption.
Main Results:
- Significant magnetic field enhancement of NO2 gas response (0.5-100 ppm) at room temperature.
- Gas response positively correlated with magnetic field strength and NO2 concentration.
- Nearly four-fold increase in response to 500 ppb NO2 at 150.8 mT, with sensitivity rising from 8 to 30.
Conclusions:
- Magnetic fields effectively enhance the sensitivity of Co3O4 gas sensors for NO2 detection.
- Magnetic field-induced adsorption enhancement on cobalt sites is the key sensing mechanism.
- Magnetic field modulation offers a generalizable strategy to improve conventional metal oxide gas sensors.
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