Ultrathin Pd Pt Rh Nanorings with Strong C-C Bond Breaking Ability for the Ethanol Oxidation Reaction.

Ethanol as a fuel for direct ethanol fuel cells (DEFCs) has the advantages of being highly energetic, environmentally friendly, and low-cost, while the slow anodic ethanol oxidation reaction (EOR), intermediate poisoning effect, and incomplete oxidation of ethanol became obstacles to the development of DEFCs. Herein, a 2D ternary cyclic Pd Pt Rh nanorings (NRs) catalyst with efficient EOR performance is prepared via a facile one-pot solvothermal approach, and systematic studies are carried out to reveal the mechanisms of the enhanced performance and C-C bond selectivity. In particular, the optimized catalyst exhibits impressive mass activity, stability, toxicity resistance, and C-C bond cleavage ability. It's proposed that the considerable performance is attributed to the unique hollow structure, providing abundant active sites. The high toxicity resistance is not only attributed to the electronic modulation of the catalyst material by Rh atoms, but also depends on the excellent water activation properties of Rh, which contribute to the removal of intermediates, such as CO. In addition, the density functional theory calculations showed that the introduction of Rh significantly enhances the C-C bond cleavage ability of the catalyst, further improving the EOR activity.