Influence of chloride ion on zinc electrodeposition from choline chloride based deep eutectic solvent

When deep eutectic solvent (DES) is used to recycle Zn from zinc-containing dusts, chlorine present in these dusts will enter into the resulting solution and inevitably affects subsequent electrodeposition of zinc. This paper investigated the effect of added chloride ions on the electrodeposition behavior of zinc from choline chloride-urea-ethylene glycol (ChCl-urea-EG) DES-containing zinc oxide. Compared with the blank ChCl-urea-EG DES, the addition of chloride ion is found to increase the current efficiency, reduce the energy consumption, and improve the compactness of Zn deposits. In addition, cyclic voltammetry results and kinetic parameters lead to the conclusion that the added chloride ions have an inhibiting effect on Zn(II) ion migration, but have a promoting effect on reduction reaction of Zn(II) ion. The results of X-ray diffraction analysis reveal that the addition of chloride ions affects the crystallographic orientation by enhancing the growth of (101), (102), and (103) planes.