Modifications induced in structural, electronic and dielectric properties of Nd2NiMnO6 double perovskite by Sr doping

Herein, the structural, electronic, dielectric and electrical properties of Nd2NiMnO6 have been tailored by doping divalent Sr at the site of trivalent Nd. All the samples of Nd2−xSrxNiMnO6 (x = 0.0, 0.1, 0.3) show monoclinic structure that can be indexed with P21/n space group. The degree of disorder in the samples due to Sr doping has been confirmed through Raman spectroscopy which suggest an increase in disorder with increase in concentration of Sr. The Sr doping and oxygen vacancies induce the formation of different charge states of Ni and Mn and hence there is mixed valence of Ni2+, Ni3+, Mn2+, Mn3+ and Mn4+ as confirmed through the X-ray photoemission spectroscopy. Dielectric studies on all the samples of Nd2−xSrxNiMnO6 (x = 0.0, 0.1, 0.3) suggest the decrease of dielectric constant as well as dielectric loss with increase in frequency. Moreover, increase in temperature also leads to the increase in dielectric constant as well as dielectric loss in all the samples. Conductivity and impedance studies have been investigated for all the three samples of Nd2−xSrxNiMnO6 (x = 0.0, 0.1, 0.3) and the results obtained are inter-related with each other. •No change in structure with increase in concentration of Sr is depicting the phase stability of compounds.•Presence of mixed valence of Ni and Mn in all the three samples of Nd2−XSrXNiMnO6 (X = 0.0, 0.1, 0.3).•Oxygen vacancies are responsible for irregular trends shown by conductivity and impedance with increasing concentration of Sr.•Confirmation of Negative temperature coefficient of resistance and semiconducting behavior.•Increase in dielectric constant with increase in concentration of Sr depicting the potentiality of compounds in energy storage devices.