Interactions between co-adsorbed CO and H on a Rh(100) single crystal surface.

Co-adsorption of CO and H(2) on a Rh(100) single crystal surface has been studied by a combination of temperature programmed desorption (TPD), reflection absorption infrared spectroscopy (RAIRS), low energy electron diffraction (LEED), and density functional theory (DFT) calculations. Exposure of CO to a hydrogen precovered surfaces at 150 K results in some displacement of adsorbed hydrogen and a layer with 0.67 ML H and 0.67 ML CO is obtained. A c(3 square root(2) x square root(2))R45 degree structure is formed with CO occupying bridge sites and hydrogen occupying partly bridge sites on the surface and partly octahedral subsurface sites, causing hydrogen to desorb at temperatures around 230 K.

Direct catalytic route to superhydrophobic polyethylene films.

Polyethylene films grow on a flat silica surface modified by the bis(imino)pyridyl iron(II) catalyst during ethylene polymerization in toluene solvent. The resulting films show superhydrophobic properties. Advancing water contact angle as high as 169 degrees and sliding angles as low as 2 degrees are obtained on these films. SEM images reveal special surface structures of these films containing micrometer-sized islands, submicrometer particles on the islands, and stress nanofibers between the islands, which render superhydrophobicity to the polyethylene surfaces. After the submicrometer particles and stress nanofibers are removed by annealing, the superhydrophobic properties of the polymer films disappear.