Study of Physical Properties of Co Substituted GdFeO3 Orthoferrites and Evaluation of Their Antibacterial Activity

Abstract

Perovskite-type GdFe1‒xCoxO3 (0.00 ≤ × ≤ 0.25) solid solution is prepared with the citrate auto combustion technique. The electrical properties and the Seebeck coefficient are measured in the temperature range 300–600 K to elucidate the Co doping effect on the physical properties of the GdFeO3. The variation of the magnetic susceptibility (χ) with the absolute temperature as a function of different magnetic fields is investigated. The data reveals that the samples under investigation are G-type antiferromagnetic with a weak ferromagnetic moment results due to a slight canting. The decrease of the molar magnetic susceptibility χ with the temperature ensures the presence of a weak ferromagnetic behavior originated from the Dzyaloshinskii–Moriya interaction. The ac conductivity (σac) is increased by increasing the frequency and follows Jonscher’s power law. For the investigated samples, the non-overlapping small polarons are responsible for the conduction in the low- temperature region. While at high temperatures, the correlated barrier hopping (CBH) mechanism takes place. The Seebeck coefficient changes from a negative to a positive value with increasing Co2+ ion concentration and increases with rising temperature up to 550 K. The total variation of the Seebeck coefficient signifies the p-type conduction (holes) as charge carriers along with the designated temperature range. The antibacterial activity of the investigated samples is studied. Finally, the obtained data demonstrates the crucial role of doping in improving the multiferroic properties, which would open up the possibility of using GdFe1‒xCoxO3 in fabricating magnetic field sensors and data storage devices.