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Nanosized Sodium-Doped Lanthanum Manganites: Role of the Synthetic Route on their Physical Properties

Lorenzo Malavasi·Maria C. Mozzati·Stefano Polizzi·Carlo B. Azzoni·Giorgio Flor
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Abstract

In this paper we present the results of the synthesis and characterisation of nanocrystalline La1-xNaxMnO3+delta samples. Two synthetic routes were employed: polyacrylamide-based sol-gel and propellant synthesis. Pure, single phase materials were obtained with grain size around 35 nm for the sol-gel samples and around 55 nm for the propellant ones, which moreover present a more broaden grain size distribution. For both series a superparamagnetic behaviour was evidenced by means of magnetisation and EPR measurements with peculiar features ascribable to the different grain sizes and morphology. Preliminary magnetoresistivity measurements show enhanced low-field (< 1 T) magnetoresistance values which suggest an interesting applicative use of these manganites.

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Lorenzo Malavasi, Maria C. Mozzati, Stefano Polizzi, Carlo B. Azzoni, Giorgio Flor. 2003-10-17. Nanosized Sodium-Doped Lanthanum Manganites: Role of the Synthetic Route on their Physical Properties. https://arxiv.org/abs/cond-mat/0310411

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