Insight into the Metal-Support Interactions between Ruthenium and Nanodiamond-derived Carbon material for CO Oxidation

摘要

For supported metal catalysts, metal-support interactions (MSI) are vital for their catalytic performance, which can be regulated by controlling surface structures of supports. In this work, two kinds of nanodiamond (ND)-derived carbon materials, i. e. ND@graphene (ND@G) and onion-like carbon (OLC), were applied to support Ru catalyst. The characterization results show that compared with OLC supported Ru catalyst (Ru/OLC), ND@G supported Ru catalyst (Ru/ND@G) exhibits a higher Ru dispersity, large amount of nanoclusters and Ru single atoms with positive charges dispersing on the surface of ND@G, indicating a stronger MSI in Ru/ND@G. Ru/ND@G favors twin CO adsorbates, while Ru/OLC favors linear adsorbates. For CO oxidation reaction, it was found that Ru/OLC with more metallic Ru NPs exhibited higher catalytic activity compared to Ru/ND@G. Moreover, Ru/OLC showed better reusability and stability compared to Ru/ND@G during CO oxidation reaction. This work highlights the importance of having an adequate rather than an excessively strong MSI for some catalytic systems.