Yttrium doped cobalt ferrite nanoparticles: Study of dielectric relaxation and charge carrier dynamics. Issue 12 (15th August 2018)

• Record Type: Journal Article
• Authors: Chakrabarty, S.; Pal, M.; Dutta, A.
• Is Part Of: Ceramics international. Volume 44:Issue 12(2018)
• Page Start: 14652
• Page End: 14659
• Publication Date: 2018-08-15
• Subjects: Chemical route -- Nanoparticles -- UV–vis -- Scaling -- Dielectric response; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2018.05.091
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: We report the effect of yttrium (Y) doping on structural, optical properties and conductivity relaxation behavior of cobalt ferrite (CFO) nanoparticles prepared via citrate auto-ignition route. Microstructural analysis using XRD study confirms the growth of single phase nanocrystalline CFO, HRTEM images delineate faults in the crystal stacking sequence. UV–vis absorption spectra show a blue shift for optical band gaps of the doped samples. Impedance spectroscopy suggests that both grain and grain boundaries contribute to the conduction process. A universal power law dependence of the conductivity spectra has been observed. Scaling of the conductivity spectra resulted the conduction mechanism to be independent of composition and temperature. Stretched behavior of the dielectric response has been elucidated by Harviliak-Negami (H.N.) model based functions. Defects in the crystal structure played important role on the overall transport properties of the system. Highlights: Single phase nanocrystalline Y doped cobalt ferrite were synthesized via facile chemical route. UV–vis study indicates a blue shift for optical band gap when doped with Y. Conductivity relaxation is of non-Debye type and analyzed using H.N. model function. Optimum for conductivity and dielectric dispersion were observed when Y is 15%.