Impact of platinum doping on the structural, cation distribution, electrical and dielectric properties of CoZn nanospinel oxides


Almessiere M., Ünal B., Baykal A., Demir Korkmaz A., Shirsath S. E., Gondal M. A., ...More

Materials Chemistry and Physics, vol.348, 2026 (SCI-Expanded, Scopus)

  • Publication Type: Article / Article
  • Volume: 348
  • Publication Date: 2026
  • Doi Number: 10.1016/j.matchemphys.2025.131644
  • Journal Name: Materials Chemistry and Physics
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC
  • Keywords: Cation distribution, Cole-cole study, Conductivity, Dielectric properties, Nanospinel oxides
  • Istanbul Gelisim University Affiliated: Yes

Abstract

This study explores the structural and electrochemical properties of Pt-doped cobalt–zinc nanospinel oxides (Co0·5Zn0·5Pt3xAl2-4xO4 NSOs, 0.00 ≤ x ≤ 0.10) synthesized via a sol–gel combustion route, with a focus on tunable electrical behavior for energy-related applications. Phase-pure spinel formation was confirmed by XRD, while SEM/EDX analyses verified nanoscale morphology and composition. Systematic investigation of frequency- and temperature-dependent conductivity, dielectric, and impedance responses revealed that moderate Pt substitution (x ≈ 0.02–0.06) significantly enhances charge mobility through defect-assisted transport, while higher substitution levels introduce additional relaxation phenomena and interfacial polarization. Modulus and Cole–Cole analyses confirmed a transition from Debye-to non-Debye-type relaxation, indicating a compositional control of grain and grain boundary contributions. These findings demonstrate that Pt doping provides a strategy for tuning electrical heterogeneity and dielectric response in CoZn–Al spinels, making them promising candidates for energy storage devices and sensing applications.