Non‐fluorinated Zinc Anions: A Low‐Cost Environmental Approach for Reversible Zinc Electrochemistry

Rechargeable zinc batteries (RZBs) are of immense interest as low-cost and sustainable energy storage devices. However, formation Zn dendrites, corrosion, undesired side reactions in aqueous electrolytes well the use costly fluorinated salts organic electrolytes, have hindered commercialization RZBs. In this work, a cost-efficient environmentally friendly, non-aqueous electrolyte comprised dicyanamide (Zn(dca)2) dimethyl sulfoxide (DMSO) is shown to support electrochemical cycling zinc. Fourier-transform infrared (FT-IR) spectroscopy complemented with theoretical studies suggest that solvation Zn2+ stabilized both [dca]− anions DMSO molecules at high concentrations (≥1.0 M) salt content. Stable charge/discharge cycles symmetrical cells low overpotentials (0.05 V) were especially observed for 1.0 M Zn(dca)2/DMSO over 90 mA cm−2 scanning electron microscopy (SEM) images confirming dense smooth morphology on metal anode surface post-cycling. X-ray photoelectron (XPS) also shows presence nitride (Zn3N2) helps form stable SEI layer 2.5 systems, making [dca]-based highly promising candidates rechargeable batteries.