Aqueous electrocatalytic small-molecule valorization trilogy

Small-molecule aqueous electrocatalytic transformation powered by renewable electricity is a sustainable and eco-friendly energy utilization technique for producing compounds with added value from renewable feedstocks. Although an aqueous solution can directly contribute a hydrogen/oxygen source via water splitting to the transformation process, the single active source results in fewer available reaction pathways and a narrower range of products. To overcome this difficulty, we have here summarized a three-stage electrocatalytic method for valuing aqueous small molecules based on benefit increments and different reaction pathways: (1) the primary hydrogen/oxygen as the active species participated in small-molecule selective transformation processes, (2) the external nucleophile/electrophile induced small-molecule electrocatalytic coupling transformation process, and (3) multiple steps of small-molecule electrocatalytic cascade transformation via coupling electrocatalysis with electro/thermo/biocatalysis processes. Finally, we discuss the present challenges and knowledge gaps, thus setting the trajectory for future advances in aqueous electrocatalytic small-molecule valorization.