Relaxation behavior, charge transport mechanisms and electromagnetic properties of hard/soft CoFe2O4@ZnSmxFe2-xO4 spinel ferrite nanocomposites: AC/DC conductivity, modulus formalism
European Physical Journal Plus, cilt.141, sa.11, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 141 Sayı: 11
- Basım Tarihi: 2026
- Doi Numarası: 10.1140/epjp/s13360-026-08522-7
- Dergi Adı: European Physical Journal Plus
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- İstanbul Gelişim Üniversitesi Adresli: Evet
Özet
The Hard/Soft CoFe2O4@ZnSmxFe2-xO4 (x ≤ 0.10) spinel ferrite nanocomposites (H/S CFO@Sm → ZFO (SF) NCs) have been synthesized via sol–gel method. The products were characterized by XRD (X-ray powder diffractometry), SEM along with EDX (Scanning Electron Microscopy along with Energy Dispersive X-ray Spectroscopy), TEM (Transmission Electron Microscopy), HR-TEM (High-Resolution Transmission Electron Microscopy), Impedance spectroscopy and Microwave absorption algorithm. The cubic crystal structure, sphere morphology and chemical composition were confirmed by XRD, SEM–EDX and TEM analyses respectively. Sm3+—substituted NCs exhibited improved shielding characteristics compared with the undoped NCs. It is evident to observe that Sm3⁺ ion-substitution causes to enhance AC conductivity (σAC) up to x = 0.08 by increasing ferrous/ferric ion-hopping pairs, whereas at x = 0.10, both lattice distortions and insulating secondary phases affect the conduction mechanisms. Moreover, the DC conductivity (σDC) exhibits a non-linear, V-shaped Arrhenius dependence, with semiconducting behavior at high temperatures and anomalous metallic-like conduction at lower temperatures. Also, dielectric parameters such as the dielectric loss and dielectric constant spectra indicate Maxwell–Wagner interfacial polarization, while resonance-like anomalies are quite evident at higher Sm3⁺ ion-content level. Similarly, complex electric modulus and its Nyquist analyses disclose non-Debye relaxation, with depressed arc indicative of dispersive relaxation times. Consequently, these results underscore the tunability of charge-carrier transport and dielectric behavior via rare-earth (RE) substitution, making these multi-ferrites NCs attractive for high-frequencies, electronic devices, and energy-storage applications.