Polysulfide modified PtCu intermetallic nanocatalyst with enrichment realizes efficient electrooxidation ethanol to CO₂

The main problem faced by ethanol oxidation reaction (EOR) includes low activity, poor selectivity, and durability. In the study, we found that polysulfide modified on the surface of PtCu intermetallic (IM)/C can simultaneously enrich hydroxyl and ethanol, which could effectively improve the catalytic activity, CO₂ selectivity, and durability of catalyst. The mass activity and the specific activity of the product in 1 M KOH electrolyte reached 17.83 A·mg_Pt⁻¹ and 24.67 mA·cm⁻². The CO₂ selectivity of polysulfide modified product achieved 93.5%, which was 30 folds higher than Pt/C. In addition, the catalyst showed high catalytic stability. The mechanism study demonstrates that the surface modified polysulfide could significantly boost the enrichment effect of ethanol and hydroxyl species, accelerating C–C bond cleavage and CO oxidation.