Electrical conductivity of cobalt-doped BaZn hexagonal ferrites

Abstract Electrical conductivity and mobility studies of BaZn 2− x Co x Fe 16 O 27 ( x =0.0, 0.2, 0.5, 0.7, 0.9, 1.1 and 1.3) hexagonal ferrites as a function of composition and temperature range 300–600 K are reported. The negative sign of these compositions indicated the n-type conduction which is predominantly due to the hopping of electrons between Fe 2+ and Fe 3+ ions at the octahedral sites. The mobility increases with rising temperature which is attributed to enhancing the rate of hopping electrons. The thermoelectric power increases as the cobalt concentration increases up to x =1.1 and then decreases for higher concentration. This is attributed to spin up position for x x >1.1.