A Novel Sensor for the Detection of n-Butanol Based on CoMn₂O₄ Nanoparticles

In this paper, we studied the alcohol-sensing properties of CoMn₂O₄ nanoparticles for the first time. The CoMn₂O₄ nanoparticles were prepared via a simple microwave-assisted colloidal method using cobalt nitrate, manganese nitrate, dioctyl sulfosuccinate sodium salt, and ethylene glycol as a solvent. Various techniques were used to characterize the structural, morphological, and optical properties of CoMn₂O₄. The crystal structure of CoMn₂O₄ was found after calcination at a temperature of 400 °C. The Raman spectrum showed seven vibrational bands, while the optical absorption spectrum showed three bands, confirming the spinel CoMn₂O₄. Morphological analysis revealed that the porous microstructure of CoMn₂O₄ was composed of nanoparticles with a size distribution of 16 to 58 nm. Gas sensors were fabricated with the CoMn₂O₄ powders calcined at 400 °C using the brush-coating method, and experimental results showed that CoMn₂O₄ nanoparticles were more sensitive to n-butanol than isopropanol and ethanol at an operating temperature of 185 °C. The CoMn₂O₄ sensor showed a response of 6.6 at 50 ppm n-butanol with good stability, reproducibility, and repeatability. The present article provides a new sensing material that could be used as an n-butanol sensor with significant benefits for human health.