Dispersed surface Ru ensembles on MgO(111) for catalytic ammonia decomposition.

Ammonia is regarded as an energy vector for hydrogen storage, transport and utilization, which links to usage of renewable energies. However, efficient catalysts for ammonia decomposition and their underlying mechanism yet remain obscure. Here we report that atomically-dispersed Ru atoms on MgO support on its polar (111) facets {denoted as MgO(111)} show the highest rate of ammonia decomposition, as far as we are aware, than all catalysts reported in literature due to the strong metal-support interaction and efficient surface coupling reaction.

High Loading of Transition Metal Single Atoms on Chalcogenide Catalysts.

Transition metal doped chalcogenides are one of the most important classes of catalysts that have been attracting increasing attention for petrochemical and energy related chemical transformations due to their unique physiochemical properties. For practical applications, achieving maximum atom utilization by homogeneous dispersion of metals on the surface of chalcogenides is essential. Herein, we report a detailed study of a deposition method using thiourea coordinated transition metal complexes.

Self- regeneration of Au/CeO based catalysts with enhanced activity and ultra-stability for acetylene hydrochlorination.

Replacement of Hg with non-toxic Au based catalysts for industrial hydrochlorination of acetylene to vinyl chloride is urgently required. However Au catalysts suffer from progressive deactivation caused by auto-reduction of Au(I) and Au(III) active sites and irreversible aggregation of Au(0) inactive sites. Here we show from synchrotron X-ray absorption, STEM imaging and DFT modelling that the availability of ceria(110) surface renders Au(0)/Au(I) as active pairs.

Control of reactivity through chemical order in very small RuRe nanoparticles.

The choice of suitable organometallic precursors, [Re(CH)] and [Ru(Me-Allyl)COD] or [Ru(COD)(COT)], allows us to synthesize polyvinylpyrrolidone (PVP) stabilized bimetallic RuRe nanoparticles of ca. 1.3 nm with narrow size dispersity, displaying the hcp crystal structure and to control their chemical order: an alloy or Re rich surface.

Facile synthesis of ultra-small rhenium nanoparticles.

Ultra-small monodisperse rhenium nanoparticles (Re NPs; ca. 1.0-1.

On the influence of diphosphine ligands on the chemical order in small RuPt nanoparticles: combined structural and surface reactivity studies.

Diphenylphosphinobutane (dppb) stabilized bimetallic RuPt nanoparticles were prepared by co-decomposition of [Ru(COD)(COT)] [(1,5-cyclooctadiene)(1,3,5-cyclooctatriene)ruthenium] and [Pt(CH(3))(2)(COD)] [dimethyl(1,5-cyclooctadiene) platinum(II)] organometallic precursors under mild conditions (room temperature, 3 bar of dihydrogen) and in the presence of dppb. The determination of the nanoparticles' chemical composition was made possible thanks to a combination of several characterization techniques (HREM, STEM-HAADF, WAXS, EXAFS, IR, NMR) associated with surface reactivity studies based on simple catalytic reactions. The obtained nanoparticles display a ruthenium rich core and a disordered shell containing both ruthenium and platinum.

In situ formed catalytically active ruthenium nanocatalyst in room temperature dehydrogenation/dehydrocoupling of ammonia-borane from Ru(cod)(cot) precatalyst.

The development of simply prepared and effective catalytic materials for dehydrocoupling/dehydrogenation of ammonia-borane (AB; NH(3)BH(3)) under mild conditions remains a challenge in the field of hydrogen economy and material science. Reported herein is the discovery of in situ generated ruthenium nanocatalyst as a new catalytic system for this important reaction. They are formed in situ during the dehydrogenation of AB in THF at 25 °C in the absence of any stabilizing agent starting with homogeneous Ru(cod)(cot) precatalyst (cod = 1,5-η(2)-cyclooctadiene; cot = 1,3,5-η(3)-cyclooctatriene).

One-pot synthesis of colloidally robust rhodium(0) nanoparticles and their catalytic activity in the dehydrogenation of ammonia-borane for chemical hydrogen storage.

Rhodium(0) nanoparticles stabilized by tert-butylammonium octanoate were prepared reproducibly from the reduction of rhodium(II) octanoate with tert-butylamine-borane in toluene at room temperature and characterized by ICP-OES, TEM, HRTEM, STEM, EDX, XRD, XPS, FTIR, UV-vis, (11)B, (13)C and (1)H NMR spectroscopy and elemental analysis. These new rhodium(0) nanoparticles show unprecedented catalytic activity, lifetime and reusability as a heterogeneous catalyst in room temperature dehydrogenation of ammonia-borane, which is under significant investigation as a potential hydrogen storage material.