New porous materials such as zeolites, metal-organic frameworks and mesostructured oxides are of immense practical utility for gas storage, separations and heterogeneous catalysis. Their extended pore structures enable selective uptake of molecules or can modify the product selectivity (regioselectivity or enantioselectivity) of catalyst sites contained within. However, diffusion within pores can be problematic for biomass and fine chemicals, and not all catalyst classes can be readily synthesized with pores of the correct dimensions. Here, we present a novel approach that adds reactant selectivity to existing, non-porous oxide catalysts by first grafting the catalyst particles with single-molecule sacrificial templates, then partially overcoating the catalyst with a second oxide through atomic layer deposition. This technique is used to create sieving layers of Al(2)O(3) (thickness, 0.4-0.7 nm) with 'nanocavities' (<2 nm in diameter) on a TiO(2) photocatalyst. The additional layers result in selectivity (up to 9:1) towards less hindered reactants in otherwise unselective, competitive photocatalytic oxidations and transfer hydrogenations.

Selective hydrogenolysis of cyclic and linear ether C-O bonds is accomplished by a tandem catalytic system consisting of lanthanide triflates and sinter-resistant supported palladium nanoparticles in an ionic liquid. The lanthanide triflates catalyze endothermic dehydroalkoxylation, while the palladium nanoparticles hydrogenate the resulting intermediate alkenols to afford saturated alkanols with high overall selectivity. The catalytic C-O hydrogenolysis is shown to have significant scope, and the C-O bond cleavage is turnover-limiting.

A method for synthesizing metal nanoparticle catalysts with a structured environment using atomic layer deposition (ALD) has been developed. The method involves growing uniform, dispersed Pd nanoparticles, protecting the particles with a blocking agent, growing a metal oxide structure around the nanoparticle using ALD, and removing the blocking agent. Using CO adsorption and diffuse reflectance infrared Fourier transform spectroscopy, possible blocking agents for metal nanoparticles have been evaluated based on the ability of CO to adsorb to the blocking agent−Pd nanoparticle complex. Ethylenediamine and decanethiol were found to be effective blocking agents, while acetonitrile, 1-(3mercapto) propyl-3,5,7,9,11,13,15-isobutylpentacyclo[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxane, and hexafluoroacetylacetonate were less effective. Octadecanethiol was proven to be effective in protecting Pd nanoparticles during Al 2 O 3 ALD.

This work characterizes the adsorption, structure, and binding mechanism of oxygenated organic species from cyclohexane solution at the liquid/solid interface of optically flat alumina-supported palladium nanoparticle surfaces prepared by atomic layer deposition (ALD). The surface-specific nonlinear optical vibrational spectroscopy, sum-frequency generation (SFG), was used as a probe for adsorption and interfacial molecular structure. 1-Hexanoic acid is an overoxidation product and possible catalyst poison for the aerobic heterogeneous oxidation of 1-hexanol at the liquid/solid interface of Pd/Al(2)O(3) catalysts. Single component and competitive adsorption experiments show that 1-hexanoic acid adsorbs to both ALD-prepared alumina surfaces and alumina surfaces with palladium nanoparticles, that were also prepared by ALD, more strongly than does 1-hexanol. Furthermore, 1-hexanoic acid adsorbs with conformational order on ALD-prepared alumina surfaces, but on surfaces with palladium particles the adsorbates exhibit relative disorder at low surface coverage and become more ordered, on average, at higher surface coverage. Although significant differences in binding constant were not observed between surfaces with and without palladium nanoparticles, the palladium particles play an apparent role in controlling adsorbate structures. The disordered adsorption of 1-hexanoic acid most likely occurs on the alumina support, and probably results from modification of binding sites on the alumina, adjacent to the particles. In addition to providing insight on the possibility of catalyst poisoning by the overoxidation product and characterizing changes in its structure that result in only small adsorption energy changes, this work represents a step toward using surface science techniques that bridge the complexity gap between fundamental studies and realistic catalyst models.

To clarify expectations for mature cutting skills and investigate the influences of cutting task and scissor type, we videotaped 60 typical adults cutting three shapes with two different types of scissors. The videotapes were reviewed, and 38 aspects of grasp and cutting motions were rated. Percentages of participants who used a particular grip or cutting motion for each shape with each scissor type were reported and compared. Findings included variations in grasp that depended on the scissor type used and variations in cutting motions that depended on the shape being cut. Improved understanding of mature scissor skills and the effect of variations in the cutting task and scissor type used will allow more effective assessment of and intervention for children and adults with cutting difficulties. Specific implications for practice are discussed.