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Detailed study of structural, optical, dielectric and electrical properties of Ni0.7Cd0.3Cr2O4 (NCCO) chromite prepared using sol-gel method

  • Original Paper: Sol-gel and hybrid materials for optical, photonic and optoelectronic applications
  • Published:
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Abstract

In this report, the new polycrystalline spinel-type chromite Ni0.7Cd0.3Cr2O4 (NCCO) was successfully synthesized by sol-gel process. This sample is characterized by X-Ray diffraction (XRD), optical analysis by DRS spectroscopy and dielectric measurements. The X-ray diffraction (XRD) analysis reveals that the prepared sample is well crystallized in the Fd3̅m space group. Optical results from the reflectance spectrum shows indirect band gap energy that was also evaluated from the reflectance spectra using the Kubelka-Munk function and Marotti’s approach, the Egind is found close to 1.64 eV. The variations of Urbach energy (Eu), the penetration depth (δ), extinction coefficient (K) and refractive index (n) were clearly determined and discussed. The Ac impedance spectroscopy type Agilent model 4294 A was used to examine the dielectric and electrical transport properties over a wide temperature (200 K-400 K) and frequency range (100 Hz to100KHz). The obtained results demonstrate that the electrical conductivity (σ) correlates with the Jonscher power law that indicates a semiconducting behavior and confirm the ′′non-overlapping small polaron tunneling, ′′NSPT′′ model of our sample. The activation energy is estimated to be Ea = 0.529 eV based on the study of continuous conductivity. The behavior of permittivity (ε’,ε”) and the loss coefficient tgδ was attributed to Wagner’s Maxwell theory of interfacial polarization. The imaginary part of the impedance curve (Z′′) shows a dielectric relaxation phenomenon in the present compound. The Nyquist plots show a monotonic decrease in grain resistance (Rg) and grain boundary resistance (Rgb) with increasing temperature. This result confirms that the transport mechanism in the chromite NCCO is governed by the effect of grain boundaries. These analysis prove that our sample may be a good candidate for optoelectronics devices.

Graphical Abstract

Highlights

  • Ni0.7Cd0.3Cr2O4 (NCCO) was successfully synthesized by sol–gel technic.

  • X-ray diffraction (XRD) analysis confirm that our sample is well crystallized in the Fd3̅m group.

  • Reflectance spectrum shows indirect band gap energy that is found close to 1.64 eV.

  • Refraction index of our spinel chromite NCCO is n = 1.7.

  • Electrical conductivity (σ) correlates with the Jonscher power law and confirm the non-overlapping small polaron tunneling, “NSPT” model.

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-This paper has not been published before; that it is not under consideration for publication anywhere else.

- The publication of this work has been approved by all co-authors, if any, as well as by the responsible authorities.

-The publisher will not be held legally responsible should there be any claims for compensation.

Code availability

-The preparation of sample under supervision JK was done in the Research Unit ofValuation and Optimization of Resource, Faculty of Science and Technology of Sidi Bouzid.

-Structural and morphology analysis was done under supervision JK and MLB at Prince Sattam Bin Abdulaziz University.

-Dielectric and optical measurements was made on Laboratory of Physics of Materials and Nanomaterials Applied to the Environment (LaPhyMNE), Faculty of Sciences of Gabes under supervision JK and KK.

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Acknowledgements

The authors acknowledge the support of the Tunisian Ministry of Higher Education and Scientific Research in the field of scientific research and technology.

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Authors and Affiliations

  1. Research Laboratory of Technology, Energy and Innovative Materials, TEMI, Faculty of Sciences of Gafsa University of Gafsa, Gafsa, 2112, Tunisia

    Hanen Dhibi

  2. Higher Institute of Applied Sciences and Technology of Gabes ISSAT, Uinversity of Gabes, Gafsa, 6072, Tunisia

    Omar Rejaiba

  3. Research Unit Advanced Materials, Applied Mechanics, Innovative Processes and Environment, Gabes ISSAT, Uinversity of Gabes, Gafsa, 6072, Tunisia

    J. Khelifi

  4. Faculty of Science and Technology of Sidi Bouzid, University of Kairouan, University Campus Agricultural City, 9100, Sidi Bouzid, Tunisia

    M. Nasri

  5. Laboratoire de Physique des Matériaux et des Nanomatériaux Appliquée à l’Environnement, Faculté des Sciences de Gabès cité Erriadh, Université de Gabès, 6079, Gabès, Tunisia

    Omayma Amorri & Kamel Khirouni

  6. Department of Mechanical Engineering, College of Engineering, Prince Sattam Bin Abdulaziz, University, Alkharj, 11942, Saudi Arabia

    Mohamed Lamjed Bouazizi

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Contributions

HD: writing, conceptualization, funding acquisition, formal analysis. OR: conceptualization, funding acquisition, formal analysis, writing—review and editing. JK: conceptualization, formal analysis, writing—review and editing. MN: conceptualization, formal analysis, writing—review and editing. OA: conceptualization, formal analysis, writing—review and editing. KK: funding acquisition, formal analysis. MLB: funding acquisition.

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Correspondence to Omar Rejaiba.

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Dhibi, H., Rejaiba, O., Khelifi, J. et al. Detailed study of structural, optical, dielectric and electrical properties of Ni0.7Cd0.3Cr2O4 (NCCO) chromite prepared using sol-gel method. J Sol-Gel Sci Technol 108, 159–174 (2023). https://doi.org/10.1007/s10971-023-06178-8

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