Single-Atom Gold Catalysis in the Context of Developments in Parahydrogen-Induced Polarization

• Published in: Chemistry : a European journal Vol. 21; no. 19; pp. 7012 - 7015
• Main Authors: Corma, Avelino, Salnikov, Oleg G., Barskiy, Danila A., Kovtunov, Kirill V., Koptyug, Igor V.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 04.05.2015; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: Catalysis; Catalysts; Chemistry; Fluid dynamics; Gold; heterogeneous catalysis; Hydrogen storage; Hydrogenation; Multi wall carbon nanotubes; Nanotechnology; Nanotubes; NMR spectroscopy; Polarization; signal enhancement; gold; heterogeneous catalysis; NMR spectroscopy; hydrogenation; signal enhancement
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201406664

A highly isolated monoatomic gold catalyst, with single gold atoms dispersed on multiwalled carbon nanotubes (MWCNTs), has been synthesized, characterized, and tested in heterogeneous hydrogenation of 1,3‐butadiene and 1‐butyne with parahydrogen to maximize the polarization level and the contribution of the pairwise hydrogen addition route. The Au/MWCNTs catalyst was found to be active and efficient in pairwise hydrogen addition and the estimated contributions from the pairwise hydrogen addition route are at least an order of magnitude higher than those for supported metal nanoparticle catalysts. Therefore, the use of the highly isolated monoatomic catalysts is very promising for production of hyperpolarized fluids that can be used for the significant enhancement of NMR signals. A mechanism of 1,3‐butadiene hydrogenation with parahydrogen over the highly isolated monoatomic Au/MWCNTs catalyst is also proposed. The hydrogens went in 2 by 2: Hydrogenation of 1,3‐butadiene and 1‐butyne with parahydrogen is carried out by using a highly isolated heterogeneous monoatomic gold catalyst supported on multiwalled carbon nanotubes. The percentage of pairwise hydrogen addition is found to be approximately 10 % for this catalyst in which the catalytically active center is a single atom.