Surface oxygen vacancies, dynamically created and annihilated under the reaction conditions, may serve as a unique form of active site for heterogeneous catalysis. In this study, mechanisms selected reactions (i.e., CO oxidation, water-gas shift, CO2 hydrogenation, alcohol carbonation, selective catalytic reduction NO with NH3) proposed by in-situ spectroscopy characterizations were reviewed to...

An experimental approach for the production of catalyst-free hyperpolarised ethanol solution in water via heterogeneous hydrogenation of vinyl acetate with parahydrogen and the subsequent hydrolysis of ethyl acetate was demonstrated. For an efficient hydrogenation, liquid vinyl acetate was transferred to the gas phase by parahydrogen bubbling and almost completely converted to ethyl acetate wit...

The mechanistic understanding and control over transformations of multi-unsaturated hydrocarbons on transition metal surfaces remains one of the major challenges of hydrogenation catalysis. To reveal the microscopic origins of hydrogenation chemoselectivity, we performed a comprehensive theoretical investigation on the reactivity of two α,β-unsaturated carbonyls-isophorone and acrolein-on seven...

Introduction Hydrogenation of carbon monoxide to produce hydrocarbons, normally called Fischer-Tropsch synthesis (F-T synthesis), is one of the most important hydrogenation reactions due to its potential for the intermediate production of hydrocarbon fuels in the “postpetroleum” era. The reaction is favored at low-temperature and therefore reducing the particle size of the catalyst to several n...

The governing mechanism of surface reactions is a fundamental concern in heterogeneous catalysis. The Langmuir–Hinshelwood (LH) mechanism is widely accepted to control the surface reactions in many catalytic systems. This contribution derives and compares several important surface rate equations to evaluate their quality of fitting to the experimental data collected for a vapor-phase hydrogenat...

The Pd(111) crystal was attached to a motorized manipulator using tantalum wires and could be heated by means of electron bombardment to 900 K or cooled to 77 K, as monitored by a T1T2 thermocouple attached directly to the sample. It was cleaned by cycles of Ar sputtering (4 keV, 7 μA) and annealing (850 K) followed by brief heating to ~ 850 K in the presence of 2×10 mbar of O2 to remove residu...

Chiral diols with three contiguous stereocenters were synthesized by a highly enantioselective ruthenium-catalyzed asymmetric hydrogenation of racemic α,α'-disubstituted cycloketones involving dynamic kinetic resolution. This new catalytic asymmetric method provides a concise route to the alkaloid (+)-γ-lycorane.

[reaction: see text]. A novel catalytic system for asymmetric hydrogenation of functionalized ketones has been developed using a Pd/bisphosphine complex as the catalyst in 2,2,2-trifluoroethanol. The reaction exhibits high enantioselectivity, and up to 92.2% ee was obtained.

Although 1,3-butadiene hydrogenation is known to be a structure-sensitive reaction, correlation of the catalytic activity with the exact Pd particle surface structure shows that the reaction is in fact particle size independent.

The Pt colloid supported on carbon is an active and selective catalyst for the partial hydrogenation of nitroaromatics with electron-withdrawing substituents to the corresponding N-arylhydroxylamine, indicating an additive-free green catalytic approach for arylhydroxylamine synthesis.