A Simple and Versatile Approach for the Low-Temperature Synthesis of Transition Metal Phosphide Nanoparticles from Metal Chloride Complexes and P(SiMe3 )3.

Metal chloride complexes react with tris(trimethylsilyl)phosphine under mild condition to produce metal phosphide (TMP) nanoparticles (NPs), and chlorotrimethylsilane as a byproduct. The formation of Si-Cl bonds that are stronger than the starting M-Cl bonds acts as a driving force for the reaction. The potential of this strategy is illustrated through the preparation of ruthenium phosphide NPs using [RuCl2 (cymene)] and tris(trimethylsilyl)phosphine at 35 °C. Characterization with a combination of techniques including electron microscopy (EM), X-ray absorption spectroscopy (XAS), and solid-state nuclear magnetic resonance (NMR) spectroscopy, evidences the formation of small (diameter of 1.3 nm) and amorphous NPs with an overall Ru50 P50 composition. Interestingly, these NPs can be easily immobilized on functional support materials, which is of great interest for potential applications in catalysis and electrocatalysis. Mo50 P50 and Co50 P50 NPs can also be synthesized following the same strategy. This approach is simple and versatile and paves the way toward the preparation of a wide range of transition metal phosphide nanoparticles under mild reaction conditions.

Synthesis and structures of homoleptic germylenes and stannylenes with sulfonimidamide ligands.

An unusual series of germylenes and stannylenes with homoleptic symmetric and unsymmetric N-substituted sulfonimidamide ligands PhSO(NiPr)(NHiPr) 1 and PhSO(NMes)(NHiPr) 2 have been prepared by protonolysis reaction of Lappert's metallylenes [M(HMDS)2] (M = Ge or Sn) with two equivalents of the appropriate sulfonimidamide. The homoleptic germylenes [PhSO(NiPr)2]2Ge 3 and [PhSO(NMes)(NiPr)]2Ge 4, and stannylenes [PhSO(NiPr)2]2Sn 5 and [PhSO(NMes)(NiPr)]2Sn 6 were fully characterized by NMR spectroscopy and by X-ray diffraction analysis. DFT calculations have been performed to understand the electronic properties brought by the sulfonimidamide ligand.

The five shades of oleylamine in a morphological transition of cobalt nanospheres to nanorods.

Understanding of cobalt nanorods' (Co NRs) formation still remains challenging when it comes to enhancing their anisotropic properties applicable in magnetic or catalytic areas. Herein, we propose a mechanism for the morphological transition from spherical cobalt nanoparticles (NPs) to Co NRs over time (9 h) in a mixture of [CoCl(PPh3)3] and oleylamine (OAm). In the literature, we described how spherical Co NPs are synthesized via a disproportionation process. Based on in situ and pseudo in situ observations, two steps of this unique mechanism are characterized first by the dissolution of the spheres and then the regrowth in rods' shape in the presence of an OAm template. Furthermore, ex situ experiments show that these steps are the result of interdependent reactions occurring between Co NPs, cobalt(ii) and OAm. The latter plays numerous roles in this synthesis: as a surfactant, a disproportionation promoter, and a hydrogen source allowing the reduction of cobalt(ii) complexes; its ammonium salt derivative is involved in oxidative etching of Co NPs and it promotes the anisotropic growth in NRs. These coupling actions of reduction and etching generate two cobalt reservoirs of nuclei under thermodynamic conditions.

Symmetric and non-symmetric bis-metallylene iron complexes, precursors of iron germanide nanoparticles.

We report herein the synthesis of symmetric and non-symmetric bis-amidinato-germylene Fe(CO)3 complexes, as well as the preparation of the corresponding disymmetric germylene-stannylene and germylene-silylene complexes by selective displacement of a carbonyl ligand under UV-a light irradiation. The symmetric bis-germylene Fe(CO)3 complex has been applied in the synthesis of iron germanide nanocrystals.

Designed single-source precursors for iron germanide nanoparticles: colloidal synthesis and magnetic properties.

The synthesis of iron germanide nanoparticles at the nanoscale is a challenging task. Here, we describe the preparation of nanocrystals of the hexagonal Fe1.67Ge phase via the thermolysis of single source precursors [{iPrNC(tBu)NiPr}RGe]Fe(CO)4 (where R = Cl, N(SiMe3)2) under mild conditions (200 °C). These bimetallic precursors and the corresponding germylenes [{iPrNC(tBu)NiPr}RGe] were fully characterized by spectroscopic techniques as well as single crystal X-ray diffraction. While the structural features of the molecular species were shown to be almost identical, the results of the thermolysis were highly dependent on the nature of R. When R = Cl, multimodal size distributions and non-controlled phases were obtained. In contrast, the thermolysis of [{iPrNC(tBu)NiPr}{N(SiMe3)2}Ge]Fe(CO)4 yielded pure ferromagnetic Fe1.67Ge nanoparticles with a mean diameter close to 6 nm and a narrow size distribution (<12%). These results were rationalized in terms of Ge-substituent bond energy thanks to a computational study.