We report a tunable organometallic synthesis of monodisperse iron carbide and core/shell iron/iron carbide nanoparticles displaying a high magnetization and good air-stability. This process based on the decomposition of Fe(CO)(5) on Fe(0) seeds allows the control of the amount of carbon diffused and therefore the tuning of nanoparticles magnetic anisotropy. This results in unprecedented hyperthermia properties at moderate magnetic fields, in the range of medical treatments.

The performance of well-defined ultrasmall iron(0) nanoparticles (NPs) as catalysts for the selective hydrogenation of unsaturated C-C and C=X bonds is reported. Monodisperse iron nanoparticles of about 2 nm size are synthesized by the decomposition of {Fe(N[Si(CH3)3]2)2}2 under dihydrogen. They are found to be active for the hydrogenation of various alkenes and alkynes under mild conditions and weakly active for C=O bond hydrogenation.

Ultrasmall FeRu bimetallic nanoparticles were prepared by co‐decomposition of two organometallic precursors, {Fe[N(Si(CH3)3)2]2}2 and (η4‐1,5‐cyclooctadiene)(η6‐1,3,5‐cyclooctatriene)ruthenium(0) (Ru(COD)(COT)), under dihydrogen at 150 °C in mesitylene. A series of FeRu nanoparticles of sizes of approximately 1.8 nm and incorporating different ratios of iron to ruthenium were synthesized by varying the quantity of the ruthenium complex introduced (Fe/Ru=1:1, 1:0.5, 1:0.2, and 1:0.1). FeRu nanoparticles were characterized by TEM, high‐resolution TEM, and wide‐angle X‐ray scattering analyses. Their surface was studied by hydride titration and IR spectroscopy after CO adsorption and their magnetic properties were analyzed by using a superconducting quantum interference device (SQUID). The FeRu nanoparticles were used as catalysts in the hydrogenation of styrene and 2‐butanone. The results indicate that the selectivity of the nanoparticle catalysts can be modulated according to their composition and therefore represent a case study on fine‐tuning the reactivity of nanocatalysts and adjusting their selectivity in a given reaction.

FeRu nanoparticles were prepared according to an organometallic route using {Fe[N(Si(CH 3) 3) 2 ] 2 } 2 and (g 4-1,5-cyclooctadiene)(g 6-1,3,5-cyclooctatriene) ruthenium(0) Ru(COD)(COT) precursors followed by their insertion into a mesoporous MCF-17 support host. The resulting nanoparticles had a uniform size of approximately 2 nm, with a relative Ru amount of up to 33 at.%. Steadystate Fischer-Tropsch catalysis at 6 bar total pressure (H 2 / CO = 1:1) demonstrated light olefins production with a selectivity close to 50 % (ex. CO 2) for catalysts with low Ru content (5 at.%). The selectivity pattern changed to long chain-paraffin production with increasing Ru amounts. These catalysts were also more active than those containing few Ru. X-ray photoelectron spectroscopy showed under-parity Ru amounts to effectively cover the surface of Fe nanoparticles. The nanoparticle distribution inside the MFC-17 host was characterized by microtomia/ transmission electron microscopy.

The syntheses of some novel fluorinated and nonfluorinated hydroxyborate salts, [Q]+[HOB(C6F5)3]− and [Q]+[HOBPh3]− ([Q]+ = aprotic cation), are reported. The reactivities of both salts with group IV metal complexes were compared. The reaction of [PPN]+[HOB(C6F5)3]− ([PPN]+ = bis(triphenylphosphoranylidene)ammonium) with Cp2ZrMe2 and Cp2HfMe2 resulted in the formation of the ionic complexes [PPN]+[Cp2ZrMe(OB(C6F5)3)]− and [PPN]+[Cp2HfMe(OB(C6F5)3)]− in high yields. These complexes were fully characterized, and the covalent characteristics of the M–O and B–O bonds were established by X-ray crystallographic structural determination.

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Monodisperse iron nanoparticles of about 2 nm size are prepared and tested as a heterogeneous catalyst in the hydrogenation of alkenes, dienes, and alkynes.

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