PEGylated Quasi-Ionic Liquid Electrolytes: Fundamental Physiochemical Properties and Electrodeposition of Aluminum

PEGylated quasi-ionic liquid electrolytes were obtained by simply mixing organic/inorganic salts and low molecular-weight poly(ethylene glycol) (PEG 200, 300, 400) at room temperature. There were 14 salts investigated in this paper, and most of them were soluble in PEGs. The different solubilities of salts in PEGs may be due to their interactions between the composed organic cations/anions and the PEG chains. The proposed quasi-ionic liquids were proven to have good physiochemical properties including negligible volatility, low viscosity (about 50 mPa s), intrinsic conductivity, and wide electrochemical window (>2.5 V). Moreover, the electrolytes can be used inter alia for electrochemical applications, such as the electrodeposition of aluminum. Homogeneous, high-purity, adherent aluminum layers were obtained at low potential (-0.2 V) and room temperature (303.15 K). The developed PEGylated quasi-ionic liquid electrolytes offer a new system to easily co-deposit the active metal, such as Zn, Mg with high performance at low potentials.