The ethanol oxidation reaction (EOR) has drawn increasing interest in electrocatalysis and fuel cells by considering that ethanol as a biomass fuel has advantages of low toxicity, renewability, and a high theoretical energy density compared to methanol. Alternatively, the ethanol electroreforming is a low energy cost technology that may produce valuable chemicals in the anode and clean hydrogen in the cathode at low temperature and atmospheric pressure. In both of the above energy conversion and storage technologies, the efficient oxidation of the ethanol in the anode by means of electrocatalysis is essential and the efficiency is largely determined by the chosen catalysts. Notably, in alkaline media both Pt and Pd show enhanced EOR activities.

The mechanistic investigation as well as the rational design of electrocatalysts are challenging yet essential for the desired complete oxidation to CO₂, in considering that EOR is a complex multiple-electron process involving various intermediates and products. This talk starts with discussion on the mechanistic understanding of EOR on Pt and Pd surfaces using selected publications as examples. Consensuses from the mechanistic studies are that sufficient active surface sites to facilitate the cleavage of the C–C bond and the adsorption of water or its residue are critical for obtaining a higher electro-oxidation activity. I will then show by cases how this understanding has been applied to achieve improved performance on Pt- and Pd-based catalysts for EOR in alkaline media through optimizing electronic and bifunctional effects, as well as by tuning their surface composition and structure.

Acknowledgements：Financial support from the NSFC (grant No. 21733004 and 21473039）and the 973 Program (No. 2015CB932303) of MOST is highly appreciated

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[6] X.Y. Ma, Y.F. Chen, Q.X. Li, W.F. Lin, W.B. Cai, to be submitted.