MnFe₂O₄ as a gas sensor towards SO₂ and NO₂ gases

The chemical co-precipitation method was used to synthesize MnFe₂O₄ nanoparticles. Single cubic phase formation of nanoparticles was confirmed by X-ray diffraction technique. The average particle size of MnFe₂O₄ nanoparticles was found to be 10.7 nm using Scherrer formula. The ultrafine powder of MnFe₂O₄ nanoparticles was pressed to design pellet of 10 mm diameter and 1mm thickness. Copper electrodes have been deposited on the surface of pellet using silver paste in the form of capacitor. Fabricated gas sensing device of MnFe₂O₄ nanoparticles was tested towards SO₂ and NO₂ gases. Cole-Cole plot of MnFe₂O₄ was investigated with the help of electrochemical workstation. The performance of the sensors including sensitivity, response and recovery time was also determined. It was observed that the MnFe₂O₄ nanoparticles are more sensible for NO₂ gas as compared to SO₂ gas.