The In Situ Electrochemical−Chemical Cascade Strategy for Pyruvic Acid Synthesis

ABSTRACT

Hydrogen peroxide (H ₂ O ₂ ), as a green oxidizing medium, can be generated and utilized in situ via an electrochemical–chemical cascade, enabling organic transformations while enhancing efficiency and selectivity. However, balancing high H ₂ O ₂ production, efficient activation, and selective substrate conversion remains challenging. Herein, a series of transition metal‐doped CeO ₂ catalysts were developed for electrocatalytic H ₂ O ₂ generation and its subsequent use in converting α‐hydroxy acids to pyruvate. Among them, Ni−CeO ₂ exhibited the best performance, achieving a pyruvate production rate of 19.9 mmol g ⁻¹ h ⁻¹ and a Faradaic efficiency of 55.3%. Mechanistic studies revealed that transition metal doping regulates the local coordination environment and oxygen vacancy concentration, thereby optimizing the adsorption strength of the *OOH intermediate, which governs the two‐electron oxygen reduction reaction pathway and H ₂ O ₂ generation and release. Furthermore, in situ generated H ₂ O ₂ was selectively activated on the catalyst surface to form a reactive oxygen species network dominated by hydroxyl radicals (·OH) and assisted by singlet oxygen ( ¹ O ₂ ). Among these, ·OH showed the lowest energy barrier for α‐C─H bond activation and subsequent electron rearrangement, making it the key species for pyruvate formation. This work provides a new strategy for the preparation of value−added chemicals.