0000000000754855
AUTHOR
P. Decorse
Fundamental and technological aspects of the surface properties and reactivity of some metal oxides
Abstract As is usually accepted for many inorganic compounds, the surface properties often play a fundamental role in the overall properties of metal oxides, in particular when the oxide materials are used in the form of fine grains. One difficulty in characterizing these surface properties is to apply the results of studies performed on ideal surfaces to the actual materials in use. A way to accept this challenge can be to successively consider initial powders, polycrystalline pellets formed after thermal or mechanical treatment of these powders and, finally, monocrystalline surfaces prepared from these powders or pellets. This principle can be applied to the study of the surface propertie…
A dilatometric study of the Lao.8Sr0.2MnO3 sintering behaviour
Abstract The sintering behaviour of La0.8Sr0.2MnO3 has been studied by dilatometry between 1100 and 1800 K in various oxygen potentials [pure oxygen, air and nitrogen (PO2 = 1 × 10−5 bar)]. The starting material was prepared by spray pyrolysis of aqueous solutions of nitrates. Two classical sinter stages, neck formation and grain growth respectively, were evidenced from dilatometric curves and this result was corroborated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The rate of densification was found to be directly dependent on oxygen partial pressure, the best conditions being in nitrogen. These results are discussed in terms of vacancy diffusion and oxygen …