Impact of aluminum on the Seebeck coefficient and magnetic properties of La0.7Ba0.3MnO3 manganites

Abstract

• Al effect on the thermopower and magnetic susceptibility of La 0.7 Ba 0.3 MnO 3 compound. • The composites are still a single phase rhombohedral despite adding Al 2 O 3 phase. • Power factor values decrease with increasing Al content. • (LaBaMnO) 0.975 /(AlO) 0.025 composite record the highest value of power factor. • TEP data satisfy the Magnon and Phonon drag model and SPH conduction mechanism. The effect of aluminum on (La 0.7 Ba 0.3 MnO 3 ) 1-x /(Al 2 O 3 ) x composites is investigated based on their crystal structure, thermoelectric power and magnetic properties. The X-ray diffraction process reveals that the composite still exhibits a rhombohedral perovskite structure R 3 ¯ C of all composites. The thermoelectric power data satisfies the Magnon and Phonon-drag models in the low-temperature range, and the smaller Polaron conduction mechanism in the high-temperature range. The power factor values decrease with Al content and the x = 0.025 record the highest value. All composites undergo ferromagnetic to paramagnetic transition at a certain temperature T C . The AC susceptibility values decrease with the increasing Al content.