Electrically and magneto-dielectrically modified La3+ doped Co0.3Li0.1Ca0.5Fe2.1-xLaxO4 spinel ferrites and their potential applications

Abstract

Low temperature and more efficient sol-gel auto combustion process was utilized to synthesize Co0.3Li0.1Ca0.5Fe2.1-xLaxO4 [La-CLCF] spinel ferrites (where x = 0.00, 0.01, 0.02, 0.03, 0.04, and,0.05). The La-CLCF sample's structural, optoelectrical, dielectric, and magnetic properties were examined as a result of La3+ doping. All synthesized La-CLCF samples have single-phased spinel matrix, according to X-ray diffraction (XRD) analysis. It was found that the crystallite size was 11 nm, and the bandgap energy of 3.45 eV for La3+ doping x = 0.03. The resistivity and activation energy both were increased with the substitution of La3+ in the CLCF spinel matrix, while the peak position of temperature coefficient of resistance (TCR) percentage was − 3.92%/K at 372 K for sample x = 0.03. The alternating current conductivity improves with frequency, whereas the dielectric constant and tangent loss decrease as frequency increases. Further, the saturation magnetization and the microwave operating frequency for all the samples were reduced with the doping of La3+. The minimum coercivity was 242 Oe at x = 0.03. Our study suggested that the Co0.3Li0.1Ca0.5Fe2.07La0.03O4 sample is tested as an active material for potential use in high-frequency applications, electromagnetic wave absorbing material, and evaluating the sensitivity of infrared (IR) detectors used in night vision bolometers. © 2024 Elsevier B.V.

Keywords Bolometers, Crystal Structure, High-frequency, Resistivity, Tangent loss