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Colloidal Ru nanoparticles (NP) display interesting catalytic properties for the hydrogenation of (hetero)arenes as they proceed efficiently in mild reaction conditions. In this work, a series of Ru based materials was used in order to selectively hydrogenate quinaldine and assess the impact of the stabilizing agent on their catalytic performances. Ru nanoparticles stabilized with polyvinylpyrrolidone (PVP) and 1‐adamantanecarboxylic acid (AdCOOH) allowed to obtain 5,6,7,8‐tetrahydroquinaldine with a remarkable selectivity in mild reaction conditions by choosing the suitable solvent. The presence of a carboxylate ligand on the surface of the Ru NP led to an increase in the activity when compared to Ru/PVP catalyst. The stabilizing agent had also an impact on the selectivity, as carboxylate ligand modified catalysts promoted the selectivity towards 1,2,3,4‐tetrahydroquinaldine, with bulky carboxylate displaying the highest ones. [ABSTRACT FROM AUTHOR]

The bottom‐up covalent assembly of metallic nanoparticles (NP) represents one of the innovative tools in nanotechnology to build functional heterostructures, with the resulting assemblies showing superior collective properties over the individual NP for a broad range of applications. The ability to control the dimensionality of the assembly is one of the major challenges in designing and understanding these advanced materials. Here, two new organic linkers were used as building blocks in order to guide the organization of Ru NP into two‐ or three‐dimensional covalent assemblies. The use of a hexa‐adduct functionalized C60 leads to the formation of 3D networks of 2.2 nm Ru NP presenting an interparticle distance of 3.0 nm, and the use of a planar carboxylic acid triphenylene derivative allows the synthesis of 2D networks of 1.9 nm Ru NP with an interparticle distance of 3.1 nm. The Ru NP networks were found to be active catalysts for the selective hydrogenation of phenylacetylene, reaching good selectivity toward styrene. Overall, we demonstrated that catalyst performances are significantly affected by the dimensionality (2D vs. 3D) of the heterostructures, which can be rationalize based on confinement effects. [ABSTRACT FROM AUTHOR]

The preparation and structural characterization of an original Th peroxo sulfate dihydrate, crystallizing at room temperature in the form of stable 1D polymeric microfibres is described. A combination of laboratory and synchrotron techniques allowed solution of the structure of the Th(O2)(SO4)(H2O)2 compound, which crystallizes in a new structure type in the space group Pna21 of the orthorhombic crystal system. Particularly, the peroxide ligand coordinates to the Th cations in an unusual μ3‐η2:η2:η2 bridging mode, forming an infinite 1D chain decorated with sulfato ligands exhibiting simultaneously monodentate and bidentate coordination modes. [ABSTRACT FROM AUTHOR]

Abstract: Iron sulfide nanocomposites have been prepared through reactions of bis[bis(trimethylsilyl)amido]iron(II) or zerovalent iron nanoparticles (NPs) with hydrogen sulfide gas. The chemical composition of these materials was analyzed by TEM, XRD, WAXS and Mössbauer measurements. Decomposition of bis[bis(trimethylsilyl)amido]iron(II) under an H2S atmosphere in the presence of palmitic acid produces thin iron sulfide nanoflakes, which seemingly consist of Fe2S2 and Fe7S8. The sulfidation of 9 nm zerovalent iron NPs with H2S yields thin nano flakes exhibiting the same iron sulfide phases and residual iron. Remarkably, treatment of slightly larger iron NPs (13 nm) with H2S (or alternatively benzylthiol) yields well‐shaped iron–iron sulfide core‐shell particles. These particles exhibit a crystalline iron core and an amorphous iron sulfide shell, which likely consists of Fe2S2, Fe7S8 and Fe1−XS. Magnetic measurements on these core‐shell particles show a decrease of the total magnetization (compared to bulk iron) coming along with the sulfidation process. Owing to the partially preserved ferromagnetic character these iron–iron sulfide core‐shell particles were found to have magnetic heating properties. [ABSTRACT FROM AUTHOR]

The C66(COOH)12 hexa-adduct has been successfully used as a building block to construct carboxylate bridged 3D networks with very homogeneous sub-1.8 nm ruthenium nanoparticles. The obtained nanostructures are active in nitrobenzene selective hydrogenation. [ABSTRACT FROM AUTHOR]

Herein, we present a detailed study of the conversion of a nickel(II) diamide precursor to size-tunable, monodisperse nickel nanoparticles (NPs). The thermal decomposition of nickel(II) dioleylamide, synthesized either independently or in situ, resulted in the formation of Ni NPs without the coproduction of water. Mechanistic studies were conducted on the stability and reduction pathway of the NiII precursor, and on the consequent particle formation. Variations in the ratio of trioctylphosine (TOP) to nickel allowed size tunability, which resulted in nanoparticles that ranged in size from 4 to 11 nm in diameter. The DFT calculations support a mechanistic pathway that involves nickel reduction by imine formation. This water-free method was extended to the synthesis of water-sensitive M0 NPs (M=Fe, Co). [ABSTRACT FROM AUTHOR]

Pure and highly crystalline γ-Fe2O3 nanocrystals (NCs) are obtained when hydrolysis and oxidation of a FeII organometallic precursor are performed in successive steps. Their synthesis in pure alkylamine leads to NCs of about 6 nm. In aqueous solutions of poly(vinyl)pyrrolidone, such pristine NCs form aggregates of about 150 nm that exhibit a high transversal relaxivity (r2=466 mm-1 s-1) about four times higher than that of a commercial Feridex magnetic resonance imaging (MRI) contrast agent. Consequently, they provide a significant decrease in the NMR signal at very short echo time (8 ms), which is of paramount importance in clinical practice because of the reduced duration of MRI measurements. [ABSTRACT FROM AUTHOR]

Highlights from the article: Peroxide ligands coordinate to Th cations with a rare SB 3 sb - SP 2 sp : SP 2 sp : SP 2 sp bridging mode, forming infinite 1D chains decorated simultaneously with monodentate and bidentate sulfato ligands. Peroxide, spectroscopic techniques, structure elucidation, sulfate, thorium.