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The objective of this work is to identify optimum synthesis, compacting and sintering conditions in order to achieve a pure phase fully densified La 0.8 Sr 0.2 CrO 3 (LSC) perovskite membrane. The aqueous combustion synthesis of LSC powders was investigated over a wide range of synthesis conditions by using the metal nitrates (oxidizer)-glycine (fuel) system. The powders were pressed and sintered to create dense materials, which were characterized. It was shown that depending on fuel/oxidizer ratio, , the reaction can proceed in three different modes: Smoldering Combustion Synthesis (SCS), B0.7, with maximum temperature, T m B 600°C; Volume Combustion Synthesis (VCS), 0.7 B B1.2, 1150°C B T m B1350°C; Self-propagating High-temperature Synthesis (SHS), 1.2 B B 1.6, 800°CBT m B1100°C. In turn, the characteristics of synthesized powders depend on the combustion mode. The crystalline structure of as-synthesized powders becomes more defined as increases (amorphous for SCS; crystalline for VCS and SHS). The specific surface area decreases slightly when mode changes from SCS ( 25 m 2 g − 1 ) to VCS ( 20 m 2 g − 1 ), however, it increases substantially under SHS conditions (up to 45 m 2 g − 1 ). It was also shown that calcination is beneficial only for SCS powders, while VCS and SHS powders may be sintered directly as synthesized, thus bypassing the time and energy consuming calcination step. The measured oxygen permeation values for the membranes are comparable with the best candidate materials reported in the literature.

Gold catalysts supported on γ-Al 2 O 3 (Au/γ-Al 2 O 3 ) were prepared by deposition-precipitation of aqueous HAuCl 4 and, alternatively, by deposition of Au(CH 3 ) 2 (acac) from pentane solution. The samples were characterized by in situ XANES and temperature-programmed reduction and by their performance as CO oxidation catalysts at room temperature. The Au was found to be present as Au(III) in both as-prepared catalysts, and the Au(III) was stable upon exposure to reducing gases at room temperature. Reduction of Au(III) occurred at elevated temperatures, and the rate and extent of reduction were found to depend strongly on the reducing conditions. Water vapor facilitated reduction, but only after the sample had been reduced to some extent by CO or H 2 . Exposure of an as-prepared catalyst to a catalytically reacting mixture of CO + O 2 at 100 °C was effective in activating it, though to a lesser extent. The data indicate that zerovalent Au is necessary for catalytic activity, but there is no correlation between the activity and the extent of reduction, implying that cationic Au may play a role in the catalytic sites. Water or surface species derived from water also appears to play a significant role.