Upgrading ethylene via renewable energy-driven electrocatalysis

Ethylene oxide (EO) and ethylene glycol (EG) are two important commodity chemicals and are industrially produced from petroleum-derived ethylene via thermocatalytic processes. The overoxidation of ethylene and the implementation of high temperature and pressure lead to substantial CO₂ emission. Renewable energy-driven electrocatalysis provides a low-carbon route for upgrading ethylene under mild conditions, especially when it couples with ethylene electrosynthesis from CO₂. In this minireview, we summarize recent achievements in the selective electrocatalytic oxidation of ethylene to EO and EG. Three main reaction routes including direct electrocatalytic oxidation with water, indirect electrocatalytic oxidation with halide mediators, and tandem electrocatalytic and thermocatalytic oxidation with hydrogen peroxide intermediate, are discussed. Some representative catalyst systems and reactor designs are exemplified. We discuss the existing scientific and technical challenges of electrocatalytic ethylene upgrading in terms of reaction rate, selectivity, and long-term stability, and propose future research directions and opportunities for pushing the process towards practical application.