Functional Aqueous Zinc–Acetylene Batteries for Electricity Generation and Electrochemical Acetylene Reduction to Ethylene

The available processes for removing acetylene impurities from crude ethylene are tremendously energy-intensive. Herein, we demonstrate a novel aqueous Zn–C₂H₂ battery, which not only switches energy-consuming acetylene removal to electricity generation, but also reduces acetylene to ethylene through a unique discharge mechanism: C₂H₂+Zn+H₂O→C₂H₄+ZnO. Under a pure acetylene stream, this Zn–C₂H₂ battery exhibits an open circuit potential of 1.14 V and a peak power density of 2.2 mW cm⁻², which exceed those of reported Zn–CO₂ batteries. Even for simulated crude ethylene, the Zn–C₂H₂ battery manifests an acetylene conversion of 99.97 % and continuously produces polymer-grade ethylene with only ≈3 ppm acetylene during a long-term discharge operation. Such a functional battery is universally appliable for reducing other alkynes and generating electricity. Therefore, this work provides an effective strategy for green ethylene purification and the design of functional batteries.