Synthesis of La_(1-x)Sr_xMnO_(3+δ) Manganites by Pyrohydrolysis of Nitrates

摘要

Single-phase finely dispersed perovskite-like manganites La_(1-x)Sr_xMnO_(3+δ) (0≤ x ≤ 0.33) with an average particle size of approximately 3 μm were synthesized by the pyrohydrolytic method from a stoichiometric mixture of the corresponding metal nitrates at a temperature of 500°C in a water vapor atmosphere. The parameter δ was changed as a result of the subsequent heat treatment. It was established that the manganite La_(0.67)Sr_(0.33)Mn_(3+δ) synthesized by the pyrohydrolytic method is characterized by a more pronounced change in the magnetoresistance as compared to the manganite that had the same composition but was synthesized according to the conventional ceramic technique.