Organo-metallic electrolyte additive for regulating hydrogen evolution and self-discharge in Mg–air aqueous battery

Abstract

Recently, developing metal–air batteries with cutting-edge electrolyte modification technologies has opened up numerous possibilities for designing next-generation power sources. Herein, an organo-metallic electrolytic additive, which acts as a corrosion inhibitor and as an additive in the Mg–air battery system, was used to inhibit anodic corrosion. Indigenously prepared hexamethyl cyclotrisiloxane (D3), a semi-amorphous material, unveils 90% corrosion inhibition efficiency at 600 ppm in 3.5 wt% NaCl electrolyte due to the presence of cyclic siloxane group as a physical adsorption layer over the Mg anode. The development of the passivation D3 layer via physisorption prevents the corrosion at the Mg anode, facilitating faster ion transport by increasing the active contact area for the reaction species. The D3 modified Mg air battery system exhibited an excellent discharge capacity of 1338 mA h g⁻¹ at 1 mA cm⁻² with an anodic utilization efficiency of 60.8%. Overall, the finding on developing organometallic electrolytes will open up new directions for battery research by paving the way for improved energy storage in similar air batteries.