Ru nanoparticles stabilized by organosilane fragments: Influence of the initial Si/Ru ratio and thermal stability

The decomposition of the organometallic ruthenium precursor [Ru(COD)(COT)] (COD: 1,5-cyclooctadiene; COT: 1,3,5cyclooctatriene) in mild conditions (20 C, 3 bar H2) in n-pentane leads, in the presence of octylsilane (H3 SiC8H17) to the formation of stable Ru nanoparticles with narrow size distribution. The solids obtained after washing and drying were fully characterized by elemental analysis, TEM with EDX, infra red measurements as well as solid state C CP-MAS NMR investigations. The influence of the initial octylsilane/Ru(COD)(COT) ratio ranging from 0.2 to 2.0 was studied. It was observed that the size of the nanoparticles decreases with the initial Si/Ru ratio. The thermal stability of these nanoparticles (Si/Ru = 1) was also studied and as expected the size of the particles drastically increases after treatment under H2 at 500 C, while surprisingly under neutral atmosphere, there is only a slight increase.