Synthesis and Stabilization of Subnanometric Gold Oxide Nanoparticles on Multiwalled Carbon Nanotubes and their Catalytic activity

Small gold nanoclusters in a very narrow size distribution (1.1 ( 0.5 nm) have been stabilized onto multiwalled carbon nanotubes (MWCNT). Theoretical studies supported by XPS and 16O2 / 18O2 isotopic exchange experiments have shown that, on small gold nanoparticles (0.9 1.5 nm), dissociation of molecular O2 and formation of a surface oxide-like layer is energetically favorable and occurs at room temperature, while O2 recombination and desorption involves a larger activation barrier. CO titration experiments and theoretical studies demonstrate that the reactivity of the oxidized particles toward CO does not only depend on particle size but also on oxygen coverage. The oxidation reduction process described is reversible, and the oxidized nanoparticles are active in the epoxidation of styrene with airFinancial support by the Spanish MICINN (MAT2009-14528-C02-01 and PLE2009-0046) and CONSOLIDER Ingenio 2010-MULTICAT is gratefully acknowledged. We thank Generalitat Valenciana for funding through the PROMETEO project 2088/130 amd Generalitat de Catalunya for funding though the project VALTEC 09-01-0043. L.A. thanks the Centre de Recerca en Nanoenginyeria of the Universitat Politecnica de Catalunya for the predoctoral fellowship and B.B. thanks MICINN for the PTA2008-1108-I contract. We thank Red Espanola de Supercomputacion (RES) and Centre de Calcul de la Universitat de Valencia for computational resources and technical assistance.Alves, L.; Ballesteros, B.; Boronat Zaragoza, M.; Cabrero Antonino, JR.; Concepción Heydorn, P.; Corma Canós, A.; Correa-Duarte, MÁ.... (2011). Synthesis and Stabilization of Subnanometric Gold Oxide Nanoparticles on Multiwalled Carbon Nanotubes and their Catalytic activity. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY. 133(26):10251-10261. https://doi.org/10.1021/ja202862kS10251102611332