High-temperature Plasmonic behavior and negative permittivity in CuBi2O4: Structural, dielectric, and electrical insights
Abstract
CuBi 2 O 4 (kusachiite) spinel was successfully synthesized via a conventional solid-state reaction and confirmed by X-ray powder diffraction (XRD) to crystallize in a single-phase tetragonal structure (space group P4/nnc). Scanning electron microscopy (SEM) revealed a uniform microstructure with grain sizes around 5 μm. Dielectric measurements revealed a notable Negative Real Permittivity (NRP) behavior, with permittivity values reaching as low as ε' r = -8 × 10 4 at 653 K, transitioning to positive values at higher frequencies. A broad dielectric anomaly was observed at Tc = 553 K, indicating a phase-related transition. The activation energies derived from Arrhenius analysis of DC conductivity were 0.56 eV for T ≤ 553 K and 0.66 eV for T > 553 K. AC conductivity followed Jonscher's power law, with conduction mechanisms evolving from the correlated barrier hopping (CBH) model below 553 K to the non-small polaron tunneling (NSPT) model above this temperature. Nyquist plots showed distinct grain and grain boundary contributions below 573 K, modeled via a dual R-CPE equivalent circuit. At higher temperatures, an inductive component emerged, attributed to Cu-induced surface currents and negative ε'.These results demonstrate that CuBi 2 O 4 combines thermally activated mixed conduction with unique dielectric and inductive properties, making it a promising candidate for ENZ metamaterials, temperature-tunable plas-monic devices, and coil-free inductive components.
Related
- ZnAl2O4–ZnO heterostructured nanocomposite with giant dielectric permittivity and epsilon-negative response: frequency- and temperature-dependent dielectric behavior
- Multifunctional Ag/MoO3 hybrid nanofiller-enabled PVA/CMC nanocomposite films: complementary enhancement of structural, optical, electrical, dielectric, and antibacterial properties
- Structural, dielectric behavior, diffuse phase transition, and electrical properties of 0.7(Bi1−xSmx) FeO3–0.3BaTiO3 ceramics (x = 0.1 and 0.2)
- Molecular Electrodynamic Relaxation in Dielectric and Plasmonic Cavities
- Synergistic fabrication and investigation of electrical and dielectric properties of Fe0.01Zn0.99O@C core@shell structures: Towards an in-situ energy storage application
BibTeX
@article{gahmeri2026hightemperature,
title = {{High-temperature Plasmonic behavior and negative permittivity in CuBi2O4: Structural, dielectric, and electrical insights}},
author = {Yossr Gahmeri and Imen Gharbi and Mohamed Tliha and Obaidallah A Algethami and Jean-François Bardeau and Abderrazek Oueslati},
journal = {Inorganic Chemistry Communications},
year = {2026},
month = oct,
doi = {10.1016/j.inoche.2025.115006},
url = {https://cnrs.hal.science/hal-05784995v1},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - High-temperature Plasmonic behavior and negative permittivity in CuBi2O4: Structural, dielectric, and electrical insights
AU - Yossr Gahmeri
AU - Imen Gharbi
AU - Mohamed Tliha
AU - Obaidallah A Algethami
AU - Jean-François Bardeau
AU - Abderrazek Oueslati
PY - 2026
DA - 2026/10/07
JO - Inorganic Chemistry Communications
DO - 10.1016/j.inoche.2025.115006
UR - https://cnrs.hal.science/hal-05784995v1
AB - CuBi 2 O 4 (kusachiite) spinel was successfully synthesized via a conventional solid-state reaction and confirmed by X-ray powder diffraction (XRD) to crystallize in a single-phase tetragonal structure (space group P4/nnc). Scanning electron microscopy (SEM) revealed a uniform microstructure with grain sizes around 5 μm. Dielectric measurements revealed a notable Negative Real Permittivity (NRP) behavior, with permittivity values reaching as low as ε' r = -8 × 10 4 at 653 K, transitioning to positive values at higher frequencies. A broad dielectric anomaly was observed at Tc = 553 K, indicating a phase-related transition. The activation energies derived from Arrhenius analysis of DC conductivity were 0.56 eV for T ≤ 553 K and 0.66 eV for T > 553 K. AC conductivity followed Jonscher's power law, with conduction mechanisms evolving from the correlated barrier hopping (CBH) model below 553 K to the non-small polaron tunneling (NSPT) model above this temperature. Nyquist plots showed distinct grain and grain boundary contributions below 573 K, modeled via a dual R-CPE equivalent circuit. At higher temperatures, an inductive component emerged, attributed to Cu-induced surface currents and negative ε'.These results demonstrate that CuBi 2 O 4 combines thermally activated mixed conduction with unique dielectric and inductive properties, making it a promising candidate for ENZ metamaterials, temperature-tunable plas-monic devices, and coil-free inductive components.
SN - 1387-7003
ER -