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Abstract: Hydrogen transfer of ketones, catalyzed by highly-dispersed platinum nanoparticles supported on multi-walled carbon nanotubes (MWCNTs), was studied. Pt nanoparticles were deposited on gram quantities of non-functionalized MWCNTs by atomic layer deposition (ALD) at 300°C, using (methylcyclopentadienyl) trimethylplatinum and oxygen as precursors. TEM analysis showed that ~1.4nm Pt nanoparticles were highly dispersed on MWCNTs. The heterogeneous hydrogen-transfer reactions of acetophenone indicated that an acetophenone conversion of 100% and a 1-phenylethanol selectivity of 99.0% could be obtained with a ketone to Pt mass ratio of 24,690 and a ketone to KOH mass ratio of 22 at 150°C for 5h. The selectivity of the Pt/MWCNT catalyst was higher than that of the commercial Pt/C catalyst, due to the highly-dispersed, uniform Pt nanoparticles and the unique porous structures of the Pt/MWCNT catalyst. The high stability of the Pt/MWCNT catalyst was demonstrated by reutilization of the catalyst. The high reactivity and selectivity of this catalyst for hydrogen transfer reduction were also demonstrated for other ketones. [Copyright &y& Elsevier]

Graphical abstract Highlights • MWCNTs-supported Pt-Co bimetallic catalysts were prepared by ALD. • High conversion and high selectivity were achieved for selective hydrogenation. • The synergistic effects of Pt, Co, and MWCNTs were investigated. • The interaction between Pt and Co was important for the high selectivity. • MWCNTs worked as a “bridge”, and helped electronic transfer between Pt and Co. Abstract Highly dispersed Pt-Co bimetallic catalysts were deposited on multi-walled carbon nanotubes (MWCNTs) by atomic layer deposition (ALD). High selectivity to cinnamic alcohol (>90%) was achieved with high conversion (>90%) in hydrogenation of cinnamaldehyde over an optimized Pt-Co/MWCNTs catalyst. The catalyst also showed both high activity and high selectivity in C O activation (>90%) in selective hydrogenation reactions of other α, β‐unsaturated aldehydes, which indicated that the bimetallic catalyst was a universal and highly efficient catalyst for these kinds of reactions. Further, through a series of experiments and density functional theory (DFT) calculations, the synergistic effects of Pt, Co, and MWCNTs were investigated. The results revealed that the interaction between Pt and Co NPs worked as an important role in the high selectivity in C O activation, and the synergistic effect between Pt-Co and MWCNTs boosted greatly the activity of Pt-Co bimetallic catalysts. [ABSTRACT FROM AUTHOR]