Establishing the correlation of negative permittivity and AC conductivity of LaSrNiO ( = 0, 0.1, 0.3, 1.0) for microwave shielding applications

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2024-06, Vol.12 (23), p.8473-8484
• Main Authors: Katheriya, Tarun, Nirala, Gurudeo, Upadhyay, Shail
• Format: Article
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d4tc00064a

Negative permittivity, a phenomenon observed in certain materials, has attracted considerable interest because of its significant implications in various fields of physics and engineering. Herein, from the perspective of intrinsic properties of single-phase materials, a few compositions of the La 2− x Sr x NiO 4 system ( x = 0, 0.1, 0.3, 1.0) were synthesized using the solid-state reaction method. XRD studies showed that the solubility limit of Sr in the lattice of La 2 NiO 4 is limited (0.3 < x < 1.0). Morphological studies have revealed that average grain size and density increase with increasing Sr content. Dielectric/electrical properties were studied across a wide frequency range (20 Hz-2 MHz) and at higher temperatures (30-600 °C). All the samples have negative dielectric constant and this is attributed to plasma oscillation. The Drude model was fitted to experimental data and parameters like plasma frequency ( ω p ) and relaxation frequency ( ω τ ) were determined. The low value of activation energy (