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In this article, the results of sorbitol hydrogenolysis (15% aq. solution), done in an autoclave reactor, over Ru, Pt and Ni loaded on SBA15, carbon coated SBA15 (SBA15C), activated carbon (AcC), Na–Y, Fly Ash (FA) and hydroxyapatite (HAP) catalysts by our group, were compared to find the best metal-support combinations. The metal loading was 1 wt% for Ru and Pt, 6 wt% for Ni and the catalysts' preparations were carried out by impregnation of respective salts. The catalysts were characterized with nitrogen and hydrogen adsorption measurements and X-ray diffraction. Addition of a base (Calcium hydroxide) to the reactants' mixture increased the overall conversion and selectivities of the glycols, ethylene glycol (EG) and 1,2-propylene glycol (PG). The catalysts’ performance at 60 bar and 220 °C with the presence of base (B), evaluated by the yield of glycols (PG + EG), showed the following order:Ni/Na–Y > Ru/AcC ∼ Ru/SBA15C > Ni/HAP ∼ Ru/SBA15 > Ni/SBA15 > Ru/Na–Y > Ni/FA ∼ Ni/AcC and the yields were 57, 40, 39, 33, 31, 29, 26, 22 and 21 wt%, respectively.Na–Y appeared to be the best support, especially for Ni metal; AcC and SBA15C were good supports for Ru and Pt respectively. Reusability studies revealed that Ni on HAP was the best catalyst and exhibited only a small deactivation during four runs of loading it.

The hybrid thin film comprising ZnO and TiO2 nanoparticles deposited on single‐walled carbon nanotube (SWCNT) was prepared by sol–gel process on aluminum‐coated silicon wafer. The spin‐coated films were further processed by heat treatment followed by hydrothermal process. The synthesized materials were characterized by X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), and photoluminescence spectroscopy for band‐gap determination. The coated ZnO formed the nanodisk morphology on the surface of carbon nanotubes with TiO2 nanoparticles incorporated on Al/Si wafer. The FE‐SEM analysis before and after hydrothermal treatment with ZnO–TiO2–SWCNT/Al/Si was conducted. The surface properties of the prepared thin films were analyzed for Zn2p, Ti2p, C1s, and O1s of individual spectra by X‐ray photoelectron spectroscopy (XPS) analysis. Good reproducibility and quick response time were obtained for ultraviolet (UV) light‐sensing activity with ZnO/SWCNT and ZnO–TiO2/SWCNT nanocomposites exhibiting good hydrogen gas sensing activity. [ABSTRACT FROM AUTHOR]

The kinetics of NO adsorption and dissociation on Pd(111) surfaces and the NO sticking coefficient were probed by isothermal kinetic measurements between 300 and 525 K using a molecular beam instrument. The results are discussed with respect to the rate-limiting character of the different elementary steps of the reaction system.

Transient state kinetics of the catalytic oxidation of CO with O(2) on Pd-surfaces has been measured under isothermal conditions by using a molecular beam approach. Systematic studies were carried out as a function of reaction temperature and CO+O(2) composition. With sufficient kinetic evidence, we have demonstrated the positive influence of subsurface oxygen towards CO-adsorption and oxidation to CO(2) at high temperatures (600-900 K) on Pd-surfaces, and the likely electronic nature of the surface changes with oxygen in the subsurface. These studies also provide a direct proof for CO-adsorption with a significantly reactive sticking coefficient at high temperatures on Pd-surfaces exhibiting a significant subsurface O-coverage.