Room-Temperature Carbon Dioxide Gas Sensor Based on Co-Ferrite Nanoparticles.

Area of Science:

• Materials Science
• Nanotechnology
• Environmental Science

Background:

• Accurate carbon dioxide (CO2) monitoring is vital for environmental and indoor air quality.
• Developing sensitive and reliable CO2 sensors is an ongoing research challenge.

Purpose of the Study:

• To evaluate the CO2-sensing capabilities of cobalt ferrite (CoFe2O4) nanoparticles (NPs) at room temperature.
• To investigate the impact of relative humidity (RH) and particle size on sensor performance.

Main Methods:

• Synthesis of phase-pure CoFe2O4 NPs with an average size of 6 nm.
• Fabrication and testing of gas sensors using these NPs.
• Analysis of sensor response to varying CO2 concentrations and RH levels.

Main Results:

• The 6 nm CoFe2O4 NPs exhibited high CO2 sensitivity and a nearly linear response from 250 to 4000 ppm at 30% RH.
• Sensor performance showed stable reproducibility and reliable response/recovery.
• Higher humidity (50% RH) altered the sensing mechanism, while larger crystallite sizes (60 nm) reduced CO2 signal.

Conclusions:

• CoFe2O4 NPs are a promising material for room-temperature CO2 detection.
• Particle size and humidity significantly influence the CO2 sensing performance of CoFe2O4 NPs.
• Optimized CoFe2O4 NP-based sensors offer potential for real-life CO2 monitoring applications.