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.