2512002499
  • Open Access
  • Article

Investigation of Dielectric Behavior, Diffuse Phase Transition, and Optical Band Gap in Polycrystalline KSr0.5Fe2O4 Ceramics

  • Mohamed Mounir 1,   
  • Ibtihel Soudani 1,   
  • Samia Aydi 2,   
  • Abderrazek Oueslati 2,   
  • Abdelhedi Aydi 1,*

Received: 04 Nov 2025 | Revised: 10 Dec 2025 | Accepted: 12 Dec 2025 | Published: 23 Dec 2025

Abstract

This study investigates the dielectric phase transition and optical properties of polycrystalline KSFO (KSr0.5Fe2O4). The temperature dependence of the dielectric constant reveals clear phase-transition behavior. Diffuse phase characteristics are evaluated using the modified Curie–Weiss law and Lorentzian analysis. Dielectric analysis as a function of temperature indicates a ferroelectric–paraelectric (FE–PE) transition, evidenced by a pronounced increase in the real part of the permittivity near 480 K. At lower temperatures, the material exhibits high dielectric permittivity and low dielectric loss, highlighting its potential for energy storage applications. Optical measurements yield a direct band gap of 2.10 eV, confirming the semiconducting nature of the KSFO ceramic. Overall, these results suggest that KSFO is a promising candidate for multifunctional device applications.

References 

  • 1.

    Ravez, J.; Simon, A. Some Solid State Chemistry Aspects of Lead-Free Relaxor Ferroelectrics. J. Solid State Chem. 2001, 162, 260–265.

  • 2.

    Culita, D.C.; Simonescu, C.M.; Patescu, R.E.; et al. Effect of Surfactant Concentration on Textural, Morphological and Magnetic Properties of CoFe2O4 Nanoparticles and Evaluation of Their Adsorptive Capacity for Pb(II) Ions. Ceram. Int. 2015, 41, 13553–13560.

  • 3.

    Li, J.M.; Li, G.Z.; Bai, Z.H.; et al. Effects of Mg Doping on Multiferroic Properties of Bilayered Co1−Mg Fe2O4/PMN–PT Composite Thin Films. Ceram. Int. 2014, 40, 1933–1937.

  • 4.

    Kolekar, Y.D.; Sanchez, L.; Rubio, E.J.; et al. Grain and Grain Boundary Effects on the Frequency and Temperature Dependent Dielectric Properties of Cobalt Ferrite–Hafnium Composites. Solid State Commun. 2014, 184, 34–39.

  • 5.

    Nongjai, R.; Khan, S.; Asokan, K.; et al. Magnetic and Electrical Properties of In Doped Cobalt Ferrite Nanoparticles. J. Appl. Phys. 2012, 112, 084321.

  • 6.

    Song, J.; Gao, Y.; Tan, G.; et al. Comparative Study of Microwave Absorption Properties of Ni–Zn Ferrites Obtained from Different Synthesis Technologies. Ceram. Int. 2022, 48, 22896–22905.

  • 7.

    Sharma, R.; Thakur, P.; Sharma, P.; et al. Ferrimagnetic Ni Doped Mg-Zn Spinel Ferrite Nanoparticles for High Density Information Storage. J. Alloys Compd. 2017, 704, 7–17.

  • 8.

    Šutka, A.; Gross, K.A. Spinel Ferrite Oxide Semiconductor Gas Sensors. Sens. Actuators B Chem. 2016, 222, 95–105.

  • 9.

    Oumezzine, E.; Hcini, S.; Baazaoui, M.; et al. Structural, Magnetic and Magnetocaloric Properties of Zn0.6−xNixCu0.4Fe2O4 Ferrite Nanoparticles Prepared by Pechini Sol-Gel Method. Powder Technol. 2015, 278, 189–195.

  • 10.

    Kershi, R.M. Spectroscopic, Elastic, Magnetic and Optical Studies of Nanocrystallite and Nanoferro-Fluids Co Ferrites Towards Optoelectronic Applications. Mater. Chem. Phys. 2020, 248, 122941.

  • 11.

    Dhineshbabu, N.R.; Vettumperumal, R.; Narendrakumar, A.; et al. Optical Properties of Lanthanum-Doped Copper Spinel Ferrites Nanoparticles for Optoelectronic Applications. Adv. Sci. Eng. Med. 2017, 9, 377–383.

  • 12.

    Khan, A.A.; Javed, H.M.A.; Hussain, S.; et al. Influence of Preparation Method on Structural, Optical and Magnetic Properties of Nickel Ferrite Nanoparticles. Mater. Sci.-Pol. 2017, 35, 58–65.

  • 13.

    Zaouali, A.; Maaref, M.A.; Gassoumi, M.; et al. High Electrical Conductivity at Room Temperature of MnCo2O4 Cobaltite Spinel Prepared by Sol–Gel Method. J. Mater. Sci. Mater. Electron. 2021, 32, 1221–1232.

  • 14.

    Huili, H.; Grindi, B.; Viau, G.; et al. Effect of Cobalt Substitution on the Structure, Electrical, and Magnetic Properties of Nanocrystalline Ni0.5Zn0.5Fe2O4 Prepared by the Polyol Process. Ceram. Int. 2014, 40, 16235–16244.

  • 15.

    Bo, L.; Hu, Y.; Zhang, Z.; et al. Efficient Photocatalytic Degradation of Rhodamine B Catalyzed by SrFe2O4/g-C3N4 Composite Under Visible Light. Polyhedron 2019, 168, 94–100.

  • 16.

    Mazarío, E.; Herrasti, P.; Morales, M.P.; et al. Synthesis and Characterization of CoFe2O4 Ferrite Nanoparticles Obtained by an Electrochemical Method. Nanotechnology 2012, 23, 355708.

  • 17.

    Thakur, P.; Chahar, D.; Taneja, S.; et al. A Review on MnZn Ferrites: Synthesis, Characterization and Applications. Ceram. Int. 2020, 46, 15740–15763.

  • 18.

    Jiménez-Miramontes, J.A.; Domínguez-Arvizu, J.L.; Salinas-Gutiérrez, J.M.; et al. Synthesis, Characterization and Photocatalytic Evaluation of Strontium Ferrites Towards H2 Production by Water Splitting Under Visible Light Irradiation. Int. J. Hydrogen Energy 2017, 42, 30257–30266.

  • 19.

    Chen, Y.; Wu, Q.; Bu, N.; et al. Magnetic Recyclable Lanthanum-Nitrogen Co-Doped Titania/Strontium Ferrite/Diatomite Heterojunction Composite for Enhanced Visible-Light-Driven Photocatalytic Activity and Recyclability. Chem. Eng. J. 2019, 373, 192–202.

  • 20.

    Bouzayani, M.M.; Soudani, I.; Abdessalem, M.B.; et al. Electrical Conduction Mechanism and Dielectric Properties of the KSr0.5Fe2O4 Spinel Ferrite. J. Mater. Sci. Mater. Electron. 2024, 35, 1256.

  • 21.

    Massoudi, J.; Dhahri, E.; Khirouni, K.; et al. Magnetocaloric Effect, Dielectric Relaxor Behavior, and Evidence for Direct Magnetodielectric Behavior in Ni0.6Zn0.4Al0.5Fe1.5O4 Ceramics for High-Temperature Applications. J. Phys. Chem. C 2022, 126, 2857–2867.

  • 22.

    Cheng, Z.-Y.; Katiyar, R.S.; Yao, X.; et al. Dielectric Behavior of Lead Magnesium Niobate Relaxors. Phys. Rev. B 1997, 55, 8165–8174.

  • 23.

    Glinchuk, M.D.; Stephanovich, V.A. Dynamic Properties of Relaxor Ferroelectrics. J. Appl. Phys. 1999, 85, 1722–1726.

  • 24.

    García Zaldívar, O.; Peláiz-Barranco, A.; Calderón-Piñar, F.; et al. A Relaxation Model by Using a Relaxation Times Distribution for Relaxor Ferroelectrics. Scr. Mater. 2006, 55, 927–930.

  • 25.

    Tang, X.G.; Chew, K.-H.; Chan, H.L.W. Diffuse Phase Transition and Dielectric Tunability of Ba(ZryTi1−y)O3 Relaxor Ferroelectric Ceramics. Acta Mater. 2004, 52, 5177–5183.

  • 26.

    Fang, T.-T.; Chiu, T.-Y. Polarization Dynamics of Polar Nano-Regions in Sr0.5Ba0.5Nb2O6 Doped with Combinations of Ce and Cr. Acta Mater. 2011, 59, 1692–1699.

  • 27.

    Wu, C.-C.; Yang, C.-F. Effects of NaNbO3 Concentration on the Relaxor and Dielectric Properties of the Lead-Free (Na0.5Bi0.5)TiO3 Ceramics. CrystEngComm 2013, 15, 9097.

  • 28.

    Rayssi, C.; El.Kossi, S.; Dhahri, J.; et al. Frequency and Temperature-Dependence of Dielectric Permittivity and Electric Modulus Studies of the Solid Solution Ca0.85Er0.1Ti1−xCo4x/3O3 (0 ≤ x ≤ 0.1). RSC Adv. 2018, 8, 17139–17150.

  • 29.

    Smari, M.; Rahmouni, H.; Elghoul, N.; et al. Electric–Dielectric Properties and Complex Impedance Analysis of La0.5Ca0.5−xAgx MnO3 Manganites. RSC Adv. 2015, 5, 2177–2184.

  • 30.

    Cai, W.; Fu, C.; Gao, J.; et al. Effect of Hafnium on the Microstructure, Dielectric and Ferroelectric Properties of Ba[Zr0.2Ti0.8]O3 Ceramics. Ceram. Int. 2012, 38, 3367–3375.

  • 31.

    Ke, S.; Fan, H.; Huang, H.; et al. Lorentz-Type Relationship of the Temperature Dependent Dielectric Permittivity in Ferroelectrics with Diffuse Phase Transition. Appl. Phys. Lett. 2008, 93, 112906.

  • 32.

    Bobić, J.D.; Vijatović Petrović, M.M.; Banys, J.; et al. Electrical Properties of Niobium Doped Barium Bismuth-Titanate Ceramics. Mater. Res. Bull. 2012, 47, 1874–1880.

  • 33.

    Massoudi, J.; Bouekkeze, D.; Bougoffa, A.; et al. Structural, Elastic, Optical and Dielectric Properties of Li0.5Fe2.5 O4 Nanopowders with Different Particle Sizes. Adv. Powder Technol. 2020, 31, 4714–4730.

  • 34.

    Kubelka-Munk Equation. Springer Reference; Springer: Berlin/Heidelberg, Germany, 2011.

  • 35.

    Tauc, J.; Menth, A. States in the Gap. J. Non-Cryst. Solids 1972, 8–10, 569–585.

  • 36.

    Hadded, A.; Massoudi, J.; Dhahri, E.; et al. Structural, Optical and Dielectric Properties of Cu1.5Mn1.5O4 Spinel Nanoparticles. RSC Adv. 2020, 10, 42542–42556.

  • 37.

    Soudani, I.; Massoudi, J.; Smari, M.; et al. Research on the Physical Properties of LiMn0.5Fe2O4 Spinel Ferrites by the Combination of Optical, Magnetic, and Dielectric Behaviors. RSC Adv. 2023, 13, 9260–9272.

  • 38.

    Soudani, I.; Weslati, N.; Znaidia, S.; et al. An Experimental Investigation of Vibrational, Optical, and Dielectric Properties of Li–Mg Ferrite for Potential High-Frequency and Optoelectronic Applications. RSC Adv. 2025, 15, 26873–26885.

  • 39.

    Kalyanaraman, S.; Shajinshinu, P.M.; Vijayalakshmi, S. Determination of Optical Constants and Polarizability Studies on Ferroic Tetramethylammonium Tetracholorozincate Crystal. Phys. B Condens. Matter 2016, 482, 38–42.

  • 40.

    Souissi, H.; Taktak, O.; Khalfa, M.; et al. Experimental and Optical Studies of the New Organic Inorganic Bromide: [(C3H7)4N]2CoBr4. Opt. Mater. 2022, 129, 112513.

  • 41.

    Mnakri, M.; Gharbi, I.; Enneffati, M.; et al. Synthesis and Investigation on the Optical and Complex Impedance Analysis in LiCrO2 Prepared Using Solid-State Reaction. Mater. Today Commun. 2024, 38, 107714.

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How to Cite
Mounir, M.; Soudani, I.; Aydi, S.; Oueslati, A.; Aydi, A. Investigation of Dielectric Behavior, Diffuse Phase Transition, and Optical Band Gap in Polycrystalline KSr0.5Fe2O4 Ceramics. Photochemistry and Spectroscopy 2025, 1 (1), 4. https://doi.org/10.53941/ps.2025.100004.
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