Olefin hydrogenation by ruthenium nanoparticles in ionic liquid media: Does size matter?

Ruthenium Nanoparticles in Ionic Liquids – A Saga

“…Under 4 bars of molecular H 2 , without stirring, Ru-NPs were produced of sizes (determined from TEM images, Fig. 1) 2.3 ± 0.3 nm, 2.9 ± 0.4 nm and 3.1 ± 0.7 nm at 25 °C, 50 °C and 75 °C, respectively, further corroborating the idea of size control with temperature [60]. Shown in insets in Fig.…”

“…As previously discussed, ILs provide the opportunity to precisely control the size of Ru-NPs produced in situ, and thus this fact was used to investigate the effect of small changes in size of RuNPs on the activity and selectivity in the hydrogenation of cyclohexadiene [60]. In this study it was shown that with large size particles (3 nm) hydrogenation activity was increased, whereas smaller Ru-NPs (1 nm) favoured partially hydrogenated products.…”

“…Furthermore, these NPs were found by means of XPS to be of pure zero-valent ruthenium: The low 3p 3/2 binding energy observed in each case, 460.3 eV, and doublet separation of 22.2 eV correspond closely to metallic zero-valent ruthenium. It should be noted that XPS performed in situ in the ionic liquid, resulted in no Ru binding energies being observed, as only electrons from the top 10 nm of the material may be detected using this technique [60]. In addition to size-control by varying conditions, modulating the nature of the ionic liquid plays an important role.…”

Recyclable nanoscale copper(i) catalysts in ionic liquid media for selective decarboxylative C–C bond cleavage

“…organo-boron, organo-tin, organo-zinc) reagents. 6 Nowadays metal nanoparticles, such as ruthenium, [7][8][9][10][11][12][13][14][15] platinum, 16 iridium, [17][18][19] palladium, 5,[20][21][22][23][24][25][26][27][28][29][30][31] cobalt, 32 and iron, 33 have great potential for application 34 in homogeneous and heterogeneous catalysis, including hydrogenation, 7 hydrogenolysis, 35 Fischer-Tropsch reactions 32,36 and cross-coupling reactions. 4,5,21,23 Copper 37 and especially copper(I)oxide 38 nanoparticles combine the high catalytic activity of precious metals with easy availability and low cost.…”

Nanocatalysts for Hydrogenation Reactions

“…13 TEM analyses revealed that the particle size in this Ru-NPs was in the range of 1-3 nm. Catalytic hydrogenation of 1,3-cyclohexadiene and cyclohexene was used as a probe for the relationship between size and catalytic activity of Ru-NPs.…”