Synthesis of Sr and Mg double-doped LaAlO3 nanopowders via EDTA-glycine combined process

The objective of this work is to develop a new process to synthesize LaAlO3 nanopowders double-doped by Sr and Mg with homogenous composition. This process combines the complexing ability of EDTA with the advantages of GNP combustion technique to overcome the shortcomings of GNP, using EDTA and glycine as main complexing agent and main fuel, respectively. The precursor and calcined powders are characterized by TG-DSC, XRD, TEM/EDS and Acoustic Particle Size Analyzer (APS). Single phase perovskite-type LaAlO3 solid solution is synthesized at 750 degrees C for 3 h, which is directly converted from amorphous precursor powders without any intermediate phase formation. After calcined at 1000 degrees C for 3 h, the median particle size of La0.90Sr0.1Al0.97Mg0.03O3-delta (LSAM) powders is about 136 nm measured by APS. The maximum shrinkage value of 20.6% and relative density of 95% are obtained sintered at 1600 degrees C for 5 h for 1000 degrees C-calcined LSAM powders. The total conductivity of 7.87 x10(-3) S cm(-1) at 800 degrees C for LSAM electrolyte is measured by AC impedance spectroscopy techniques in air. (C) 2012 Elsevier B.V. All rights reserved.