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Prompt [gamma] activation analysis (PGAA) has been further developed to analyze reacting components inside a chemical reactor. The new method, in situ PGAA, was used to determine the hydrogen-to-palladium molar ratio under various conditions of palladium-catalyzed alkyne hydrogenation. The H/Pd molar ratio was successfully measured in the range of 0.1-1.0 in an ~2-g catalytic reactor containing a few milligrams of palladium catalyst. The amount of hydrogen was only a few tens of micrograms, and the detection limit was ~5 [micro]g, i.e., at ppm level compared to the whole reactor. The description of the device, methodological developments, a feasibility study, and results of a series of catalytic measurements are presented.

The decomposition of ethene on the Pd(111) surface is studied by using an effusive capillary array beam doser for directional adsorption, low-energy electron diffraction (LEED), Auger electron spectroscopy (AES), temperature programmed reaction and TDS. The adsorption and decomposition of ethene and the bulk migration of the resulting carbon deposits are elucidated, which is the main focus on the Pd(111) single-crystal surface between 400 and 700 K.

A preparation of Platinum/graphite nanofiber catalyst is presented by implementing three types of GNF with Pt salt dissolved in organic solvents. Impregnation of three types of graphite nanofiber (GNF) with Pt salts resulted in catalysts with high dispersion.

Ethyl pyruvate adsorption on Pt(111) was examined at low temperature by XP and UP spectroscopy.

The intermetallic compounds [Pd.sub.3][Ga.sub.7], PdGa and [Pd.sub.2]Ga are highly selective semihydrogenation catalysts for acetylene outperforming systems. The electronic modification and isolation of active sites have caused the excellent catalytic semihydrogenation properties.

The coexistence of acidic and basic O and N sites were functionalized via amination to characterize the samples of vapor grown carbon nanofibers (VGCNFs) modified by treatment of the oxidized CNFs with N[H.sub.3]. The results revealed the potential application of the N-containing nanocarbon materials obtained via amination in catalysis as well as electronic device materials.

Nanoparticulate zirconia (Zr[O.sub.2]) has catalyzed both growth of single-wall and multiwall carbon nanotubes (CNTs) by thermal chemical vapor deposition (CVD) and graphitization of solid amorphous carbon. The studies have shown that a nonmetallic catalyst has catalyzed the CNT growth by thermal CVD while remaining in an oxidized state and has provided new insights into the interactions between nanoparticulate metal oxides and carbon at elevated temperatures.

Polarization of ethane and propane resulting from adsorption of these hydrocarbons by protons and different cations in mordenite, ZSM-5 and Y zeolite was studied by diffuse reflection Fourier transform IR spectroscopy (DRIFTS). This effect is most clearly evident for adsorbed molecules strongly perturbed through interaction with bivalent alkaline earth or zinc cations.

The adsorption and thermal deposition of Zn and ZnO on Pd(111) was examined in the temperature range between 300 and 1300K with TDS, LEED and CO adsorption technique. It was found that up to 400K, Zn multilayer adsorption on Pd(111) entirely blocks the CO adsorption sites, between 400 and 600K, multilayer bound Zn desorbs, whereas Zn atoms directly bound to Pd remain on the surface and up to 600K no hints toward alloy formation were detected by CO adsorption or LEED.

Dehydrogenation of ethylbenzene (EB) to styrene over iron oxide-based catalyst is an important industrial catalyst process. By employing gas-phase atomic hydrogen hydroxyls are prepared on alpha-Fe2O3(0001), when it is heated it reacts to produce hydrogen and water that partially reduces iron oxide.

In-situ soft X-ray absorption spectroscopy (XAS) is applied to study the iron redox behavior in over-exchanged Fe/ZSM5. The tool claims to provide new information on the geometry and valence of the Fe sites and yields an accurate method to determine the average iron valence during oxidation/reduction cycles.

The electronic structure of a practical Au/TiO2 catalyst is probed in situ by synchrotron X-ray photoelectron spectroscopy (XPS). The results have highlighted the dynamic nature of supported Au and the importance of in situ studies for the determination of gas/surface mechanisms.

One of the main stumbling blocks in developing rational design strategies for heterogeneous catalysis is that the complexity of the catalysts impairs efforts to characterize their active sites. We show how to identify the crucial atomic structure motif for the industrial Cu/ZnO/Al2O3 methanol synthesis catalyst by using a combination of experimental evidence from bulk, surface-sensitive, and imaging methods collected on real high-performance catalytic systems in combination with density functional theory calculations. The active site consists of Cu steps decorated with Zn atoms, all stabilized by a series of well-defined bulk defects and surface species that need to be present jointly for the system to work. [ABSTRACT FROM AUTHOR]

Technically relevant partial oxidation reactions represent complex reaction networks. Establishing a kinetic model for a system of multiple consecutive and parallel reaction steps is a challenging goal. The synthesis of acrylic acid by oxidation of propane using MoVTeNb mixed oxide as catalyst is such a reaction network. In an on-going study, a 10- fold parallel reactor set-up is used to vary systematically reaction conditions in a broad range over a single, well-defined MoVTeNb oxide. Selectivity and product yield in a multidimensional parameter space can give insight into the reaction network. Apparent activation energies and reaction orders of propane are derived for several conditions. Optimum reaction conditions within the investigated parameter space are specified. The results presented within this contribution contain about 200 data points measured in steady states each corresponding to reaction conditions that differ in temperature, contact time, and propane feed concentration. The fact that this data was collected in less than two months shows clearly the advantage of parallel screening of reaction conditions for mechanistic studies.