Получение и исследование сложнозамещенных манганитов лантана со структурой перовскита

Аннотация

A scientific investigation deals with obtaining of complex compounds with composition La1-2xBixSrxMn1-yNiyO3+δ (x=0.15, 0.25, y=0.0-0.4) and studying of a structure and properties. The samples were obtained by solid state reaction, citrate-nitrate method, glycine-nitrate method and co-precipitation method with different precipitants (sodium hydroxide and ammonia). A phase composition was checked using X-ray diffraction analysis. Crystallographic characteristics were calculated. Oxygen nonstoichiometry and thermal stability of the samples were studied. Particle size was determined. Porosity, surface and chip morphology of the sintered and powder samples has been studied. Linear changing of sample sizes from temperature was measured using dilatometric analysis. The value of thermal expansion coefficient was determined. The electroconductivity dependence from temperature and oxygen partial pressure was obtained for synthesized samples.