Chemical synthesis and magnetic properties of nanocrystalline (La_0.67−XGd _X)Sr_0.33MnO₃ using amorphous molecular alloy as precursors

Abstract

A new route to synthesize nanosized crystalline of (La_0.67−XGd _X)Sr_0.33MnO₃ (X=0.05, 0.10, 0.15, 0.20) perovskite-type complex oxides at calcination temperature of 600–1000 °C using the amorphous molecular alloy as precursors was reported. The precursor could be completely decomposed into complex oxide at temperature below 500 °C according to the TGA and DTA results. XRD demonstrates that the decomposed species is composed of perovskite-type structure at calcination temperature of 600 °C for 2 h. The particle size that depends on the calcination temperature of the precursor is in a range of 30–120 nm as determined by transmission electron microscopy (TEM). This method is effective and can be easily quantitatively controlled to synthesize nanosized perovskite-type complex oxides. The magnetic properties of (La_0.67−XGd _X)Sr_0.33MnO₃ nanocrystalline were preliminary studied.

Keywords

nanostructures / oxides / perovskites / chemical synthesis / magnetic properties

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