Nd substitution effects on charge transport, colossal permittivity, and X6P thermal stability of Sm2−xNdxCuO4 ceramics
- 1Faculty of Science of Bizerte, Laboratory of Physics of Materials: Structure and Property LR01ES15, University of Carthage Tunisia
- 2Faculty of Science of Bizerte, Shared Research Services Unit: Electron Microscopy (TEM) & Surface Spectroscopy, University of Carthage Tunisia
Abstract
Temperature-stable colossal permittivity ceramics are critical for high-density energy storage and power electronics operating under demanding environments. This work systematically investigates Sm2−xNdxCuO4 (x = 0, 0.2, 0.4) rare-earth cuprate ceramics synthesized via a solid-state reaction. Rietveld refinement of X-ray diffraction data confirms T′-type tetragonal structure (I4/mmm), where Nd3+ substitution expands the lattice and promotes grain growth without introducing secondary phases. Impedance spectroscopy and complex modulus analyses reveal that electrical transport is dominated by highly resistive grain boundaries (αR ≈ 0.9), exhibiting a transport crossover near 290 K to oxygen vacancy-mediated Small Polaron Hoping (Ea ≈ 0.186 eV). Notably, the optimized Sm1.6Nd0.4CuO4 ceramic achieves a remarkable negative Temperature Coefficient of Resistance (TCR ≈ −5% K−1 at 390 K), highlighting its competitive potential for uncooled thermal sensing technologies. Crucially, the x = 0.4 composition exhibits a colossal dielectric permittivity alongside low dissipation losses, driven by an Internal Barrier Layer Capacitor (IBLC) mechanism and Maxwell–Wagner interfacial polarization. Neodymium substitution effectively suppresses thermal permittivity fluctuations, restricting relative variations to over an extended operational window from −55 °C to 105 °C. this directly upgrades the material's thermal stability from the parent compound's X5R rating to the stringent Electronic Industries Alliance (EIA) X6P commercial significant. These superior characteristics position Sm1.6Nd0.4CuO4 ceramics as promising candidates for high-reliability multilayer ceramic capacitors (MLCCs) and dual-functional microelectronic devices.
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BibTeX
@article{malek2026substitution,
title = {{Nd substitution effects on charge transport, colossal permittivity, and X6P thermal stability of Sm2−xNdxCuO4 ceramics}},
author = {Missaoui Malek and Chouk Wael and Zouaoui Mouldi},
journal = {RSC advances},
year = {2026},
month = oct,
doi = {10.1039/d6ra08552k},
url = {https://europepmc.org/article/PMC/PMC13690258},
note = {CC BY},
}
RIS
TY - JOUR
TI - Nd substitution effects on charge transport, colossal permittivity, and X6P thermal stability of Sm2−xNdxCuO4 ceramics
AU - Missaoui Malek
AU - Chouk Wael
AU - Zouaoui Mouldi
PY - 2026
DA - 2026/10/22
JO - RSC advances
DO - 10.1039/d6ra08552k
UR - https://europepmc.org/article/PMC/PMC13690258
AB - Temperature-stable colossal permittivity ceramics are critical for high-density energy storage and power electronics operating under demanding environments. This work systematically investigates Sm2−xNdxCuO4 (x = 0, 0.2, 0.4) rare-earth cuprate ceramics synthesized via a solid-state reaction. Rietveld refinement of X-ray diffraction data confirms T′-type tetragonal structure (I4/mmm), where Nd3+ substitution expands the lattice and promotes grain growth without introducing secondary phases. Impedance spectroscopy and complex modulus analyses reveal that electrical transport is dominated by highly resistive grain boundaries (αR ≈ 0.9), exhibiting a transport crossover near 290 K to oxygen vacancy-mediated Small Polaron Hoping (Ea ≈ 0.186 eV). Notably, the optimized Sm1.6Nd0.4CuO4 ceramic achieves a remarkable negative Temperature Coefficient of Resistance (TCR ≈ −5% K−1 at 390 K), highlighting its competitive potential for uncooled thermal sensing technologies. Crucially, the x = 0.4 composition exhibits a colossal dielectric permittivity alongside low dissipation losses, driven by an Internal Barrier Layer Capacitor (IBLC) mechanism and Maxwell–Wagner interfacial polarization. Neodymium substitution effectively suppresses thermal permittivity fluctuations, restricting relative variations to over an extended operational window from −55 °C to 105 °C. this directly upgrades the material's thermal stability from the parent compound's X5R rating to the stringent Electronic Industries Alliance (EIA) X6P commercial significant. These superior characteristics position Sm1.6Nd0.4CuO4 ceramics as promising candidates for high-reliability multilayer ceramic capacitors (MLCCs) and dual-functional microelectronic devices.
SN - 2046-2069
ER -