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

Abstract

Abstract The objective of this work is to develop a new process to synthesize LaAlO 3 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 LaAlO 3 solid solution is synthesized at 750 °C for 3 h, which is directly converted from amorphous precursor powders without any intermediate phase formation. After calcined at 1000 °C for 3 h, the median particle size of La 0.90 Sr 0.1 Al 0.97 Mg 0.03 O 3 − δ (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 °C for 5 h for 1000 °C-calcined LSAM powders. The total conductivity of 7.87 × 10 − 3 S cm − 1 at 800 °C for LSAM electrolyte is measured by AC impedance spectroscopy techniques in air.