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–C 2 H 2 battery, which not only switches energy‐consuming acetylene removal to electricity generation, but also reduces acetylene to ethylene through a unique discharge mechanism: C 2 H 2 +Zn+H 2 O→C 2 H 4 +ZnO. Under a pure acetylene stream, this Zn–C 2 H 2 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–CO 2 batteries. Even for simulated crude ethylene, the Zn–C 2 H 2 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.