Low-temperature dielectric relaxation mechanism and correlated barrier hopping transport in neodymium perovskite chromite

Abstract

Herein, neodymium chromite (NdCrO3) has been synthesized by the sol–gel auto-combustion method. The Rietveld analysis of the X-ray diffraction pattern has shown that NdCrO3 crystalizes in the perovskite structure with orthorhombic unit cell and Pbnm space group symmetry. The electrical transport properties have been investigated by complex impedance spectroscopy over the experimental frequency and temperature ranging from 40 to 1 × 106 Hz and 158–283 K, respectively. The equivalent circuit modeling of Nyquist plots revealed the contribution of grains and grain boundaries to the charge conduction and the relaxation mechanism of NdCrO3, respectively. The AC conductivity analysis divulged the correlated barrier hopping transport mechanism in the NdCrO3. The imaginary electrical modulus spectra fitted by the Kohlrausch, Williams, and Watts function presented the non-Debye type nature of the relaxation mechanism in the material. The dielectric permittivity has exhibited the Maxwell–Wagner type polarization of the material, and the loss factor has exhibited an increasing trend with temperature.