High hydrostatic pressure effect on functional properties of nanopowder La0.6Sr0.3Mn1.1O3-δ compacts with various dispersion

Nanopowder La0.6Sr0.3Mn1.1O3−δ compacts by the oxide-salt, co-precipitation and atomization hydrolysis technologies have been obtained. Structure and its defects, average particle size and functional properties of the nanopowder compacts by X-ray diffraction, thermogravimetric, resistance, magnetic, ⁵⁵Mn NMR, magnetoresistance and BET methods have been investigated. Connections between the dispersion of nanopowders and their structural, magnetic, resistance, magnetoresistance and baroresistance properties have been established. Broad and asymmetric ⁵⁵Mn NMR spectra testify the high-frequency electron double exchange Mn³⁺↔O²⁻↔Mn⁴⁺ and indicate inhomogeneous environment of Mn by other ions and vacancies. The increase in high hydrostatic pressure up to 1.6 GPa leads to decrease in resistivity and activation energy as well as raise in density, coercive force, magnetoresistance and baroresistance effects of the nanopowder compacts.