Selective Electrocatalytic Hydrogenation of Alkynols via Hydrogen‐Mediated Isomerization for Degradable Plastics

ABSTRACT Electrocatalytic hydrogenation of alkynols is a promising approach for the manufacture of industrially important alkenols and alcohols. Nevertheless, achieving the selective hydrogenation of alkynols (especially to alcohols) via electrocatalyst design remains a challenge due to more complex C≡C/C═C hydrogenation processes. Here, we first reported the selective electrocatalytic hydrogenation of alkynols to corresponding alkenols and alcohols via a hydrogen (H*)‐mediated isomerization (HMI) mechanism. As a typical demonstration, 2‐butyne‐1,4‐diol (BYD) is successfully full‐hydrogenated to 1,4‐butanediol (BDO; with 83% selectivity) on Cu‐Cu 2 O catalyst, and semi‐hydrogenated to cis ‐2‐butene‐1,4‐diol ( cis ‐BED; with 99% selectivity) on Cu catalyst by regulating the HMI process. It is revealed that Cu‐Cu 2 O electrocatalyst with electrophilic Cu + sites can promote conversion of cis ‐BED (with nucleophilic C═C bonds) to trans ‐BED via HMI, yielding BDO. Considering that BDO is a vital monomer of poly(butylene succinate) (PBS) and it can be further oxidized to obtain succinic acid (SA; another key monomer of PBS), a coupling system to simultaneously realize the production of BDO at cathode via BYD reduction and SA at anode via BDO oxidation is designed. Moreover, PBS is successfully synthesized by polymerizing the obtained BDO and SA. Techno‐economic analysis (TEA) and life‐cycle assessment (LCA) evidence the economic feasibility and sustainability of this electrochemical process.