Chen Peng, Wang Xia, Li Dongqi, Pietsch Tobias, Ruck Michael
Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062, Dresden, Germany.
Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany.
ChemSusChem. 2022 May 20;15(10):e202200039. doi: 10.1002/cssc.202200039. Epub 2022 Apr 20.
Zinc electrodeposition is currently a hot topic because of its widespread use in rechargeable zinc-air batteries. However, Zn deposition has received little attention in organic solvents with much higher ionic conductivity and current efficiency. In this study, a Zn-betaine complex is synthesized by using ZnO and betainium bis[(trifluoromethyl)sulfonyl]imide and its electrochemical behavior for six organic solvents and electrodeposited morphology are studied. Acetonitrile allowed dendrite-free Zn electrodeposition at room temperature with current efficiencies of up to 86 %. From acetonitrile solutions in which Zn, Pb, and Cu complexes are dissolved in high concentrations, Zn and Pb/Cu are efficiently separated electrolytically under potentiostatic control, allowing the purification of solutions prepared directly from natural ores. Additionally, a highly flexible Zn anode with excellent kinetics is obtained by using a carbon fabric substrate. A rechargeable zinc-air battery with these electrodes shows an open-circuit voltage of 1.63 V, is stable for at least 75 cycles at 0.5 mA cm or 33 cycles at 20 mA cm , and allows intermediate cycling at 100 mA cm .
由于锌电沉积在可充电锌空气电池中的广泛应用，它目前是一个热门话题。然而，在具有更高离子电导率和电流效率的有机溶剂中，锌沉积很少受到关注。在本研究中，通过使用氧化锌和双[（三氟甲基）磺酰基]亚胺甜菜碱合成了一种锌-甜菜碱配合物，并研究了其在六种有机溶剂中的电化学行为和电沉积形态。乙腈在室温下可实现无枝晶锌电沉积，电流效率高达86%。在锌、铅和铜配合物高浓度溶解的乙腈溶液中，在恒电位控制下可有效电解分离锌与铅/铜，从而实现直接由天然矿石制备的溶液的净化。此外，通过使用碳纤维织物基材可获得具有优异动力学的高柔韧性锌阳极。使用这些电极的可充电锌空气电池开路电压为1.63 V，在0.5 mA cm下至少稳定循环75次，在20 mA cm下稳定循环33次，并可在100 mA cm下进行中间循环。
