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Pulsed spray evaporation chemical vapor deposition (PSE-CVD) was employed for the synthesis of cobalt-based spinel oxide thin films, Co(3-x)Fe(x)O4 with x = 0-1.56. XRD, Raman scattering and FTIR emission spectroscopy show that the normal spinel structure was retained for 0 < or = x < or = 0.65 by the selective insertion of Fe3+ in the octahedral sites. The spinel inversion was noticed above this range, whereas the insertion of Fe2+ was first indicated with x > or = 1. The room-temperature electrical resistivity of the thin films was controlled between 9 and 0.007 Omega cm by the adjustment of iron doping concentration. Furthermore an improvement of the thermal stability of the spinel was noticed upon doping by iron. The reducibility of the spinel in the presence of molecular hydrogen was efficiently adjusted by a shift of the reduction temperature by up to 110 degrees C upon the controlled insertion of iron in the octahedral sites of the spinel. The investigation of the catalytic oxidation of CO and ethanol over Co(3-x)Fe(x)O4 films with controlled structural modification enabled the confirmation of the Mars-van Krevelen mechanism for the oxidation of CO and the tight correlation between the selectivity of the conversion of ethanol to acetaldehyde and the abundance of surface basic sites. The controlled iron doping was demonstrated to be an efficient strategy to tune the reactivity and the selectivity of the cobalt-based spinel oxide. The doping-induced transition from normal to inverse spinel was observed to induce a clear discontinuity in the trend of all investigated physicochemical properties.

Tetragonal hausmannite (Mn 3 O 4 ) was synthesized by pulsed-spray evaporation chemical vapor deposition (PSE-CVD) at moderate temperatures. The thermal properties of the obtained Mn 3 O 4 thin films were evaluated with a newly developed in situ emission FTIR method. The performance of Mn 3 O 4 grown on flexible stainless steel mesh substrates was investigated toward the oxidation of CO and C 3 H 6 . X-ray diffraction (XRD) patterns, FTIR, and Raman spectroscopy reveal that only the single-phase tetragonal Mn 3 O 4 spinel structure was obtained within the temperature range of 350− 500 °C. The as-deposited Mn 3 O 4 is thermally stable up to 800 °C, and its reduction plays a determinant role in the catalytic process. Compared to conventional powder catalysts, the combination of PSE-CVD, in situ emission FTIR, and the flexible substrate provides a novel tool for catalyst synthesis and the evaluation of the thermal properties and catalytic performance.

In the past, the research in molecular separation membranes prepared through sol-gel technologies has been dominated by ceramic membranes. Especially, silica membranes have been studied in great depth. Steps towards hybrid organosilica membranes were taken by using pendant organic groups. However, only with the appearance of organically bridged silica, stable and reliable membranes that are suitable for large scale industrial utilization have become available. In this paper, we provide an overview of recent development of hybrid silica membranes that contain organic bridges. The freedom of choice in precursor allows for a flexible approach towards tailoring of the membrane properties. New support materials can be used by applying alternative deposition methods, such as expanding thermal plasma chemical vapor deposition. The robustness of the membrane concept allows for the design of novel separation process concepts in which the demonstrated stability is required.

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