学 术 报 告
Unsupported Co-based Nanoparticles as Catalysts for the Acceptorless Dehydrogenation of Acohols
Prof. Lorette Sicard
Paris Diderot University, France
Selective oxidation of alcohols into carbonyl compounds is one of the most important transformations in synthetic chemistry but it remains a difficult task. To replace traditional methods involving stoichiometric quantities of toxic oxidants such as chromium (VI) reagents, much attention has been paid to the development of catalysts using molecular oxygen as the oxidant. Another strategy, called acceptor-less dehydrogenation of alcohols (ADA), is even more attractive from the viewpoint of atom economy since it avoids the use of O2 as a hydrogen acceptor and, besides the formation of the desired carbonyl compound, the highly valuable hydrogen molecule is generated.
Co NPs are particularly interesting catalysts as their ferromagnetic properties allow an easy recovery from the reactive solution using an external permanent magnet. Unsupported tailored Co NPs have been synthesized and tested for the solvent-free acceptor-less dehydrogenation of long-chain model alcohols. Besides pure Co NPs, Co catalysts decorated with tiny Ru NPs (denoted Ru/Co) were also prepared and used for the ADA. The results show a higher catalytic stability for the Ru/Co catalyst, which can be recycled at least three times without a decrease in activity. This is explained by the promoting role of Ru, allowing keeping low valence surface states for Co.
Associate Professor Lorette Sicard obtained her Ph.D. from the CNRS-Institut Francais du Pétrole, LMM (Mulhouse University). She is the head of the “Nano-objects” department of ITODYS laboratory. Her research interests focus on synthesis of inorganic and hybrid nanomaterials by soft chemistry for catalysis environment and energy applications; study of their mechanisms of formation.