The Structure, Magnetic, and Gas Sensing Characteristics of W-Substituted Co-Ferrite Nanoparticles
Omar H. Abd‐Elkader, Abdullah M. Al‐Enizi, Shoyebmohamad F. Shaikh, Mohd Ubaidullah, Mohamed Abdelkader, Nasser Y. Mostafa
Abstract
Ferrites have been broadly investigated as gas sensors. The present article reports on the synthesis of Co-ferrite doped with W ions and their gas sensing abilities. A series of single phase CoFe2O4 powder with different W-doping (0.0 ≤ x ≤ 0.15) was synthesized using sol-gel synthesis. A variation in the saturation magnetization (Ms) and the lattice dimension with W(VI) substitution was associated with a change in the distribution of Fe(III) ions between tetrahedral and octahedral sites. Introducing W(VI) ions into the spinel lattice induced the rearrangement of Fe(III) ions. The total Ms increased with W-doping up to x = 0.05 (Ms = 50.1 Am2/kg) and it dramatically decreased to 34.6 Am2/kg with x = 0.15 of doping. However, the lattice parameter increased with increasing doping levels. Different W-doped CoFe2O4 were examined for a gas sensing response in the temperature range of 200–450 °C. Comparing the sensor responses to various reducing gases, the material’s response was shown to be sensitive and selective for acetone. The addition of W (0.15%) had a significant impact on the response and on the operating temperature of the sensor material, indicating that it might be used as an acetone sensor.