Evaluation of structural, dielectric and LPG gas sensing behavior of porous Ce3+- Sm3+ doped Cobalt nickel ferrite

• Published in: Materials chemistry and physics Vol. 275; p. 125222
• Main Authors: Srinivasamurthy, K.M., Manjunatha, K., El-Denglawey, A., Rajaramakrishna, R., Kubrin, S.P., Pasha, Apsar, Jagadeesha Angadi, V.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.01.2022; Elsevier BV
• Subjects: Cerium; Co0.5-Ni0.5 ferrites; Cobalt; Crystallites; Dispersion; Gas sensing; Gas sensors; Grain boundaries; Grain boundary; Impedance spectroscopy; Liquefied petroleum gas; LPG; Morphology; Nickel ferrites; Photomicrographs; Recovery time; Relaxation time; Room temperature; Samarium; Sensitivity; Solution combustion method; Stability analysis; Thin films; Gas sensing; Impedance spectroscopy; Solution combustion method; Co0.5-Ni0.5 ferrites; Relaxation time; Grain boundary
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2021.125222

The Co0.5Ni0.5CexSmyFe2-x-yO4 (CNCSF) XRD pattern revealed the purity of the samples without any secondary phase. The crystallite size CNCSF are in nano range. Further, the calculated lattice parameter of CNCSF are found to increasing with the RE content. From SEM micrographs surface morphology and the microstructure of the CNCSF was studied. The porous nature of the samples is revealed by SEM, which will aid in increasing their sensing response. Energy dispersive X-ray spectroscopy (EDS) patterns have confirmed the stoichiometric presence of Co2+ Ni2+, Ce3+, Sm3+ and Fe3+, those are used to prepare the CNCSF. The dielectric behaviour is similar to that of conventional spinel ferrite structures, in that the dielectric constant is highest at low frequencies and decreases at higher frequencies due to electron hopping, resulting in dielectric dispersion. Only one semicircle is seen in each Cole-Cole plot, which has uncovered that the contribution to conductivity is predominantly from the grain boundaries. At room temperature, the gas sensing responses of CNCSF thin films were investigated. For liquified petroleum gas (LPG), the gas sensing characteristics of the prepared thin films were investigated. At room temperature, the x = 0.03 thin films showed excellent sensitivity to liquified petroleum gas. The sensing response and recovery time of all of the thin films that had been prepared were reported. The sensing response of x = 0.03 thin films was highly stable over a period of 60 days on exposure to LPG (1000 PPMv), according to the stability analysis. The sample thin film with x = 0.03 can be utilized in gas sensor technology, particularly for the detection of LPG at room temperature, due to its increased sensitivity, quick response and recovery times, and stability. Pictorial representation of the material deposited on the gas substrate and gas sensing setup, SEM micrographs, The gas response in x,y = 0.0 to x,y = 0.03 thin film samples on exposure of different concentration of LPG on complete gasification and degasification process. [Display omitted] •LPG gas sensing characteristics of the Co0.5Ni0.5CexSmyFe2-x-yO4 were investigated for the first time.•The sensing response of x = 0.03 sample is stable over a period of 60 days on exposure of LPG (1000 PPMv).•The sample x = 0.03 can be utilized in the detection of LPG at room temperature.•The dielectric constant is highest at low frequencies due to electron hopping.