Preparation and magnetic properties of La0.9Ca0.1MnO3 nanoparticles at 300 °C
journal contributionposted on 01.12.2002, 00:00 by Tianhao Ji, Jiye Fang, Volodymyr Golob, Jinke Tang, Charles J. O'Connor
Nanosized La0.9Ca0.1MnO3 perovskite-type crystalline complex oxides have been prepared at the low calcination temperature of 300 °C. The preparation procedure was carried out by the two-step process of amorphous formation and calcination. The amorphous phase was obtained by the reaction of metal ions with tetrabutylammonium hydroxide at 245 °C, and then calcined at 300 °C (sample A) or 400 °C (sample B) to prepare the nanocrystalline materials. The magnetic measurement shows that spin-glass behavior exists at 45 K and the blocking temperature increases with an increase of calcination temperature. The result of the spin-glass temperature of 45 K demonstrates that the particle size of the two samples A and B is below 50 nm. The increase of blocking temperature from A to B indicates that the particle size of A is less than that of B. The measurement of the normalized resistivity versus temperature for samples A and B shows that they have the change of the normalized resistive value at 230 K.