Solvent Engineering of Oxygen‐Enriched Carbon Dots for Efficient Electrochemical Hydrogen Peroxide Production

Abstract

The development of cost‐effective and reliable metal‐free carbon‐based electrocatalysts has gained significant attention for electrochemical hydrogen peroxide (H ₂O ₂) generation through a two‐electron oxygen reduction reaction. In this study, a scalable solvent engineering strategy is employed to fabricate oxygen‐doped carbon dots (O‐CDs) that exhibit excellent performance as electrocatalysts. By adjusting the ratio of ethanol and acetone solvents during the synthesis, the surface electronic structure of the resulting O‐CDs can be systematically tuned. The amount of edge active CO group was strongly correlated with the selectivity and activity of the O‐CDs. The optimum O‐CDs‐3 exhibited extraordinary H ₂O ₂ selectivity of up to 96.55% (n = 2.06) at 0.65 V (vs RHE) and achieved a remarkably low Tafel plot of 64.8 mV dec ⁻¹. Furthermore, the realistic H ₂O ₂ productivity yield of flow cell is measured to be as high as 111.18 mg h ⁻¹ cm ⁻² for a duration of 10 h. The findings highlight the potential of universal solvent engineering approach for enabling the development of carbon‐based electrocatalytic materials with improved performance. Further studies will be undertaken to explore the practical implications of the findings for advancing the field of carbon‐based electrocatalysis.