Sol-gel synthesized Ba-Nd-Cd-In nanohexaferrites for high frequency and microwave devices applications

Abstract Nanocrystalline cadmium and indium substituted barium M-type hexagonal ferrite-based nanomaterials were prepared via sol-gel auto-combustion technique for studying the electrical, dielectric and conductivity characteristics of prepared samples such as dc resistivity, dielectric constant ( e ’ ), dielectric loss (tan δ ) and ac conductivity ( σ a c ) with the usage of different characterizing techniques like keithley 2611 two probe system and impedance analyzer. The room temperature dc resistivity of synthesized samples increases for lower concentrations i.e. x = 0.1 of Cd2+/In3+ but for the higher concentrations i.e. x = 0.2, it starts decreasing consequently. The temperature dependent dc resistivity also showing a decreasing trend as a function of temperature which continuously indicating the semi-conducting behaviour of BaM hexagonal nanohexaferrites. The room temperature dielectric characteristics was investigated as a function of logarithmic frequency and it can be explained on the basis of Maxwell Wagner model and space chare polarization. From the dielectric measurements, the dielectric constant ( e ’ ) was found to be increasing with the increasing logarithmic frequency working as good energy storage material. The dielectric loss (tan δ ) was found to be decreasing for the undoped sample (x = 0.0) but for the undoped samples (x = 0.1–0.2), it starts increasing in a very minute manner. Therefore, such materials of high increasing dielectric constant with minute values of dielectric losses make it suitable for the high frequency, energy storage and microwave devices application.