Dielectric behaviour of Zn substituted Cu nano-ferrites

• Zn substituted Cu nano-ferrite samples bearing formula Cu1−xZnxFe2O4(0≤x≤1) are synthesized by the sol–gel auto combustion method.
• The variation of real and imaginary parts of dielectric constant, dielectric loss tangent (tan δ) and AC conductivity with frequency are reported in the frequency range from 100 Hz to 120 MHz at room temperature.
• The real part of dielectric constant (ε′) decreases with increasing frequency where as the AC conductivity (σac) increases with increase in frequency. The relation of tan δ with frequency shows relaxation spectra.
• The variation in dielectric constant may be explained on the basis of space charge polarization, according to Maxwell and Wagner two-layer model.
• Dielectric constant as a function of temperature is studied at different temperatures ranging from 323 K to 583 K.

Herein, the dielectric properties such as permittivity (real part ε′ and imaginary part ε′′) and dielectric loss tangent (tan δ) are reported for Zn substituted Cu ferrites (Cu1−xZnxFe2O4; 0≤x≤1) composite using the sol–gel auto-combustion method. The variations of real and imaginary part of dielectric constant, tan δ and AC conductivity (σac) are studied at room temperature in the frequency range of 100 Hz–120 MHz. The real part of dielectric constant decrease with increasing frequency and the imaginary part (ε′′) varies with frequency showing the characteristic peak for each sample. The relation of tan δ with frequency shows relaxation spectra. Further, the σac tended to increase with increase in frequency. The variation in dielectric constant may be explained on the basis of space charge polarization, according to Maxwell and Wagner two-layer model. The dielectric constant and tan δ as a function of temperature are also studied with different temperatures ranging from 323 K to 583 K.