The effects of polyethylene glycol (PEG) as an electrolyte additive on the corrosion behavior and electrochemical performances of pure aluminum in an alkaline zincate solution

Abstract

The effects of zinc oxide and/or polyethylene glycol (PEG) as electrolyte additives on the corrosion and electrochemical performances of pure aluminum in 4.0 M KOH solutions were investigated by means of hydrogen collection, polarization curve, galvanostatic discharge, scanning electron microscopy (SEM), and energy dispersive analysis of X-ray (EDAX). The addition of ZnO markedly inhibited the corrosion of aluminum in 4.0 M KOH solutions, resulting from the deposition of zinc with high hydrogen evolution overpotential in aluminum surfaces. The introduction of PEG in the alkaline zincate solution obviously improved the deposition of zinc by increase in the overpotential of zinc deposition, thus the corrosion rate of aluminum in the alkaline zincate solutions with PEG was further decreased. The enhancement effect of PEG on the inhibition of zinc oxide first increased and then decreased with increasing the content of PEG in the electrolyte. The electrolyte system with 0.2 M ZnO and 2.0 mM PEG presented the highest inhibition efficiency (98.8%) for the corrosion of aluminum. The results of galvanostatic discharge indicated that the aluminum anode shows excellent discharge performances in the 4.0 M KOH solution with 0.2 M ZnO and 2.0 mM PEG.

Recent developments in materials for aluminum–air batteries: A review

“…Other chemical additives that have been explored include BMIMBF4, polyethylene glycol, NaSnO 3 , and alkaline citrate [58,114,[118][119][120][121]. For further information, the reader may refer to several previous reviews that have discussed in detail the additives used in alkaline media for Al corrosion inhibition [16,22,122].…”

“…Wang et al [114] and Martin and Zhu [115] evaluated the use of ZnO as an additive in KOH solutions, where as Rashvand Avei et al [116] evaluated its use in NaOH solutions. All authors claimed that the addition of ZnO helped to prevented Al corrosion and improved the performance of the Al anode.…”

Corrosion and Discharge Behaviors of Al-Mg-Sn-Ga-In in Different Solutions

“…Research results also show that Al-air batteries can use either alkaline or brine electrolytes, such as NaCl or NaOH solution ( Ref 8,14,15). The alkaline electrolyte improves Alair batteries especially ( Ref 9,12,16), however, the Al matrix is consumed invalidly by a parasitic hydrogen evolution reaction (Ref 17), as follows:…”

Corrosion behavior of 3A21 aluminum alloy in ethylene glycol solution under different atmospheres

“…Ethylene glycol is widely used as an automobile engine coolant due to its good chemical stability, low cost, excellent antifreeze properties and the ability to prevent overheating [5][6][7][8] . As reported, an alcohol film can be formed with ethylene glycol being adsorbed on the surface of aluminum alloy, which inhibits the dissolution of the anode after oxygen has been consumed [9].…”

“…The diagram of the experimental device: (1), reference electrode; (2), rotator; (3), salt bridge and Luggin capillary; (4), gas flow meter; (5), pH meter; (6), counter electrode;(7), working electrode;(8), circulating water heating system; C, connected to a condenser.…”