CO spillover on ultrathin bimetallic Rh/Rh-M nanosheets

Abstract

Rh has been regarded as a promising catalyst for ethanol-oxidation reaction (EOR). Nevertheless, Rh is vulnerable to CO poisoning. In this work, we demonstrate a facile strategy for constructing a unique class of ultrathin Rh/Rh-M nanosheets, on which CO can diffuse from the Rh site to the M site. Detailed experiments, characterizations, and theoretical simulations have been conducted to validate the CO spillover effects on Rh/Rh-M nanosheets (NSs). Moreover, the significance of the CO spillover effect has been demonstrated by catalyzing the EOR, where Rh/Rh-M NSs with CO spillover display much higher activity, higher CO2 selectivity, and stronger resistance to CO poisoning compared with pure Rh NSs. Consequently, the Faraday efficiencies (FEs) of CO2 of the optimal catalyst (e.g., Rh79Co21 NSs) are 70.3% and 75.5% at 0.7 and 0.8 VRHE, respectively, and these are much higher than those of Rh NSs (62.0% and 64.3% at 0.7 and 0.8 VRHE, respectively).