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There is a constant need for deuterium‐labelled products for multiple applications in life sciences and beyond. Here, a new class of heterogeneous catalysts is reported for practical deuterium incorporation in anilines, phenols, and heterocyclic substrates. The optimal material can be conveniently synthesised and allows for high deuterium incorporation using deuterium oxide as isotope source. This new catalyst has been fully characterised and successfully applied to the labelling of natural products as well as marketed drugs. [ABSTRACT FROM AUTHOR]

Apart from large surface areas, low activation energies are essential for efficient reactions, particularly in heterogeneous catalysis. Here, we show that not only the size of nanoparticles but also their detailed morphology can crucially affect reaction kinetics, as demonstrated for mass-selected, soft-landed, and oxidized cobalt clusters in a 6 nm to 18 nm size range. The method of reflection high-energy electron diffraction is extended to the quantitative determination of particle activation energies which is applied for repeated oxidation and reduction cycles at the same particles. We find unexpectedly small activation barriers for the reduction reaction of the largest particles studied, despite generally increasing barriers for growing sizes. We attribute these observations to the interplay of reactionspecific material transport with a size-dependent inner particle morphology. [ABSTRACT FROM AUTHOR]

Hydroformylation of olefins has been studied in the presence of specific heterogeneous cobalt nanoparticles. The catalytic materials were prepared by pyrolysis of preformed cobalt complexes deposited onto different inorganic supports. Atomic absorption spectroscopy (AAS) measurements indicated a correlation of catalyst activity and cobalt leaching as well as a strong influence of the heterogeneous support on the productivity. These new, low‐cost, easy‐to‐handle catalysts can substitute more toxic, unstable and volatile cobalt carbonyl complexes for hydroformylations on a laboratory scale. Co catalysis: A new class of low‐cost, easy‐to‐handle materials for lab‐scale hydroformylation is reported. The pyrolysis of preformed Co complexes deposited onto inorganic supports resulted in immobilised cobalt nanoparticles for oxo synthesis. The most active materials Co/phen@TiO2 and Co/phen@C represent convenient reservoirs for active homogeneous cobalt species, and thus can substitute the common, but toxic, dicobaltoctacarbonyl complex. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of Fe-based catalysts differing in surface Na/Fe ratio were prepared. • The critical role of Na is beyond its promotional effects under stationary operation. • Surface Na/Fe ratio determines the response of performance to fluctuating conditions. • Catalyst dynamics induced by fluctuating reaction conditions were studied. • The effect of Na in securing iron carbides was studied by in situ characterization. Considering the on-going developments of approaches for CO 2 capture, storage, and utilization, CO 2 hydrogenation with renewable H 2 can become sustainable technology to produce value-added chemicals/fuels in future feedstock scenarios. Herein, we investigate temporal behaviors of Fe-based catalysts in CO 2 hydrogenation under externally forced dynamics of reactor operation from the respective of composition and performance. Different catalyst preparation methods were applied to modulate the surface concentration of Na promoter but keeping the bulk concentration constant. The crucial promoter role in reserving catalyst performance and (un)steady-state catalyst composition during dynamic reactor operation was investigated by means of sophisticated catalytic tests combined with in situ and ex situ catalyst characterizations. The surface Na/Fe ratio of spent catalysts was identified as the decisive descriptor for production of the desired products under dynamic CO 2 hydrogenation conditions. The derived knowledge could be useful for redesigning catalysts and optimizing reaction processes when employing fluctuating energy supply. [ABSTRACT FROM AUTHOR]