Surface morphology, structure, and dielectric relaxation investigations of ZnO/iron nanostructures

Nanostructured metal oxide semiconductors exhibit attractive electrical properties, and, therefore, they are widely used in electronic applications. In this work, Fe-doped ZnO nanopowders were successfully synthesized via the sol–gel method. The structure of nanoparticles was characterized by scanning electron microscopy (SEM) and Fourier transform (FTIR) analysis. SEM shows very fine spherical-shaped particles in the powder, whereas FTIR shows bonding characteristics, functional groups, and intra- and intermolecular interactions. The relaxation peak is shifted towards higher frequencies with increasing temperature. The dielectric constant increases with increasing Fe concentration. Even at high temperatures, the dielectric constant is also increased due to the enhancement of the connection between the thermal motion of molecules and orientation polarization. The loss tangent decreases with increasing the temperature from 333 to 423 K. The activation energy for the relaxation is improved with increase Fe content in ZnO nanoparticles. The AC and DC conductivity gradually increases with increasing the temperature and frequency due to the increase in the number of charge carriers.