%0 Journal Article %J Advanced Science Letters %D 2011 %T Controlling stoichiometry in low temperature synthesis of La0.7Sr0.3MnO3 nanoparticles %A Azarifar, Ali %A Yadav, P. A. %A Chawla, A. K. %A Jog, Jyoti Prakash %A Patil, S. I. %A Chandra, Ramesh %A Ogale, S. B. %K Citric acid %K Complex Oxide %K Dextran %K Hexamine %K hydrothermal %X

Nanoparticles of complex oxides (<20 nm) are desirable for several applications in view of the diverse range of physical properties of such oxides. However the simultaneous presence of multiple cation precursors makes the corresponding chemical synthesis non-trivial with possible intermediate evolution of secondary phases. Such phases could react at high temperatures to form the desired stoichiometry, but this process is diffusion limited and can lead to larger particles. In this work we examine the role of three different reaction and growth controlling additives, namely dextran, citric acid and hexamine, on the synthesis of the well known colossal magneto-resistive (CMR) manganite La0.7Sr0.3MnO3. We demonstrate that phase evolutions differ significantly in the three cases, and the physical properties of the products also differ dramatically. Only dextran is shown to yield the desired phase with faceted nanoparticles at as low a temperature as 600 degrees C. A high saturation moment of similar to 47 emu/gm is realized at 10 K with a good square hysteresis loop. In 650 degrees C annealed sample, room temperature magnetization of similar to 15 emu/gm was obtained, which brings the nanoparticles in the applicability domain.

%B Advanced Science Letters %I AMER SCIENTIFIC PUBLISHERS %C 26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA %V 4 %P 424-430 %8 FEB %G eng %N 2 %3 Foreign %4 1.75 %R 10.1166/asl.2011.1230