Nanoblast Synthesis and Consolidation of (La0.8Sr0.2) (Ga0.9Mg0.1)O3-delta Under Spark Plasma Sintering Conditions

作者：Vasylkiv Oleg^*; Borodianska Hanna; Badica Petre; Zhen Yongda; Tok Alfred

来源：Journal of Nanoscience and Nanotechnology, 2009, 9(1): 141-149.

DOI：10.1166/jnn.2009.J008

• Multimetal Oxides
• LSGM
• Synthesis
• Spark-Plasma-Sintering (SPS)
• Nanopowder
• Nanoceramic
• Nanostructures
• Explosive
• Magnetoresistance

Four-cation nanograined strontium and magnesium doped lanthanum gallate (La0.8Sr0.2) (Ga0.9Mg0.1)O3-delta (LSGM) and its composite with 2 wt% of ceria (LSGM-Ce) were prepared. Morphologcally homogeneous nanoreactors, i.e., complex intermediate metastable aggregates of desired composition were assembled by spray atomization technique, and subsequently loaded with nanoparticles of highly energetic C3H6N6O6. Rapid nanoblast calcination technique was applied and the final composition was synthesized within the preliminary localized volumes of each single nanoreactor on the first step of spark plasma treatment. Subsequent SPS consolidations of nanostructured extremely active LSGM and LSGM-Ce powders were achieved by rapid treatment under pressures of 90-110 MPa. This technique provided the heredity of the final structure of nanosize multimetal oxide, allowed the prevention of the uncontrolled agglomeration during multicomponent aggregates assembling, subsequent nanoblast calcination, and final ultra-rapid low-temperature SPS consolidation of nanostructured ceramics. LaSrGaMgCeO3-delta nanocrystalline powder consisting of similar to 11 nm crystallites was consolidated to LSGM-Ce nanoceramic with average grain size of similar to 14 nm by low-temperature SPS at 1250 degrees C. Our preliminary results indicate that nanostructured samples of (La0.8Sr0.2)(Ga0.9Mg0.1)O3-delta with 2 wt% of ceria composed of similar to 14 nm grains can exhibit giant magnetoresistive effect in contrast to the usual paramagnetic properties measured on the samples with larger grain size.

• 出版日期2009-1
• 单位南阳理工学院