Gas Eruption Phenomenon Happening from Ga-In Alloy in Electrolyte

TL;DR

This study investigates a gas eruption phenomenon from Ga-In alloy in electrolyte, revealing the role of passivation layers, alloy composition, and galvanic interactions in gas generation, with implications for understanding liquid metal electrolysis.

Contribution

It uncovers the mechanism of gas eruption from Ga-In alloy in electrolyte, emphasizing the impact of passivation layer destruction and alloy composition on gas production.

Findings

Gas eruption occurs from Ga-In alloy in electrolyte.

Increased indium ratio enhances gas yield.

Passivation layer destruction is critical for gas generation.

Abstract

We report a gas eruption phenomenon caused by electrolysis of liquid Ga-In alloy in an electrolyte, especially NaOH solution. A volcanic eruption-like blowout of gas occurred from the orifice on the alloy surface. In addition to gas plume, large gas bubbles were also generated and the total gas yield increased as In ratio was increased. It is found that destructiveness of the passivation layer on the Ga-In alloy is critical to gas generation. The mechanism of gas eruption can be ascribed to a galvanic interaction happens owing to passivation film and alloy with different activity connected as electrode in electrolyte. Further investigation demonstrated that the lattice of the film expands because of the incorporation of indium, which brings about the decrease in band gap and finally enhances more gas generation. These findings regain the basic understanding of room temperature liquid metal inside electrolyte.