Effect of thermal annealing on transport properties of Fe_0.3Co_0.7S₂ Available to Purchase

Electrical resistivity and magnetoresistance studies of polycrystalline Fe_0.3Co_0.7S₂ samples prepared under different thermal treatment is presented. It shows wide distribution of Fe/Co ratio over sample volume. High temperature annealing for longer period improves the homogeneity to certain extent. The sample prepared with thermal treatment at lower temperature shows metallic behavior typical of that observed for CoS₂ compound. Whereas, resistivity increases with decrease in temperature below 143.92 K, for sample prepared at higher temperature with excess sulphur. Resistivity studies in the presence of magnetic field suggest that non-metallic behavior at low temperature may be a consequence of distribution of transition temperature over sample volume on microscopic length scale.