Dry Synthesis of Easily Tunable Nano Ruthenium Supported on Graphene: Novel Nanocatalysts for Aerial Oxidation of Alcohols and Transfer Hydrogenation of Ketones

• Published in: Journal of physical chemistry. C Vol. 117; no. 45; pp. 23582 - 23596
• Main Authors: Gopiraman, Mayakrishnan, Ganesh Babu, Sundaram, Khatri, Zeeshan, Kai, Wei, Kim, Yoong Ahm, Endo, Morinobu, Karvembu, Ramasamy, Kim, Ick Soo
• Format: Journal Article
• Language: English
• Published: Columbus, OH American Chemical Society 14-11-2013
• Subjects: Catalysis; Catalysts: preparations and properties; Chemistry; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; General and physical chemistry; Materials science; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Other topics in nanoscale materials and structures; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Thin film structure and morphology; Scanning electron microscopy; Nanoplate; Ruthenium; Nanosheet; Nanoparticle; Alcohol; Dispersive spectrometry; Ketone; X ray diffraction; Hydrogenation; Optimization; Calcining; Transmission electron microscopy; Oxidation; Raman spectrometry; Catalyst activity; Nanorod; Nanostructured materials; Catalyst
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp402978q

In this study, ruthenium nanoparticles (RuNPs) were successfully decorated on graphene nanosheets (GNSs) for the very first time by a dry synthesis method. The resultant material (GNS-RuNPs) was used as a nanocatalyst for the aerial oxidation of alcohols after being optimized. The scope of the catalytic system was extended with various aliphatic, aromatic, alicyclic, benzylic, allylic, amino, and heterocyclic alcohols. The 0.036 mol % (5 mg) of catalyst was enough for aerial oxidation of alcohols, the lowest amount of catalyst so far reported. The proposed nanocatalyst is highly chemoselective, heterogeneous, and reusable. The GNS-RuNPs were separated out from the reaction mixture and analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman, and scanning electron microscopy-energy dispersive spectrometry (SEM-EDS); the results revealed that the nanocatalyst is physically as well as chemically stable. Owing to the high stability of used catalyst (u-GNS-RuNPs), it was further applied in transfer hydrogenation, after suitable modifications. We obtained ruthenium oxide nanorod hybrid GNSs (u-GNS-RuO2NRs) from u-GNS-RuNPs by simple calcination. The catalytic activity of u-GNS-RuO2NRs toward the transfer hydrogenation of various aromatic, alicyclic, and heterocyclic ketones was found to be excellent.