Synthesis of Doped Rare Earth Manganate Perovskite Crystals Using Fused Salt Electrolysis

Abstract A facile method for the synthesis of doped lanthanum manganate crystals, suitable for the measurement of electrical and magnetic properties, is presented. Mixtures of sodium molybdate and molybdenum(VI) oxide are used as a solvent to which La 2 O 3 , MnCO 3 , and SrMoCO 4 are added as solutes which are then electrolyzed at 800–1040°C for varying lengths of time with Pt electrodes. Well-formed cubic crystals, with edge dimensions up to 1.5mm, form at the anode. Magnetization measurements show a transition to the ferromagnetic state in the temperature range ∼250–320 K, depending on the amount of aliovalent doping at the La sites. An insulator-to-metal transition is also observed in the vicinity of the ferromagnetic ordering temperature.

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