A systematic study on the effect of electron beam irradiation on structural, electrical, thermo-electric power and magnetic property of LaCoO3

• Pure and irradiated compounds follow SPH model in high temperature range.
• Colossal thermoelectric power is observed at low temperatures.
• High temperature TEP data follows SPH model.
• Curie temperature decreases with electron irradiation.
• Magnetization shows increased magnetic moment due to electron beam irradiation.

In this communication, the effect of electron beam irradiation on the structural, electrical, thermo-electric power and magnetic properties of LaCoO3 cobaltites have been investigated. Rietveld refinement of XRD data reveals that all samples are single phased with rhombohedral structure. Increase in electrical resistivity data is observed with increase in dosage of electron beam irradiation. Analysis of the measured electrical resistivity data indicates that the small polaron hopping model is operative in the high temperature regime for all samples. The Seebeck coefficient (S) of the pristine and the irradiated samples exhibits a crossover from positive to negative values, and a colossal value of Seebeck coefficient (32.65 mV/K) is obtained for pristine sample, however, the value of S decreases with increase in dosage of irradiation. The analysis of Seebeck coefficient data confirms that the small polaron hopping model is operative in the high temperature region. The magnetization results give clear evidence of increase in effective magnetic moment due to increase in dosage of electron beam irradiation.