Phase, morphology and core-level electron spectroscopy of nano-sized La_(0.65)Sr_(0.35)MnO_3 powders prepared by solution combustion synthesis

摘要

Nanocrystalline La_(0.65)Sr_(0.35)MnO_3 powders were synthesized by modified solution combustion route. The X-ray diffraction patterns of powders calcined at different temperatures were analyzed by Rietveld programme. The synthesized bulk polycrystalline sample were in 100% perovskite phase and showed an increase in particle size from 22.9 nm to 55.9 nm with the increase in the calcinations temperature from 650 °C to 850 °C. The grain boundary of sintered pellet observed under electron microscope was devoid of any precipitation related to MnO_2, SrO and the La-Mn-Sr-O phases. The core level photoelectron spectra of lanthanum, strontium, manganese and oxygen were studied in detail. The average chemical composition obtained from the XPS measurement was found to be La_(0.62)Sr_(0.38)Mn_(1.11)O_(3.44). Curie temperature for the 50 nm powder was around 365 K and saturation magnetization at 100 K was 60 emu/g.