Materials
Gallium-indium-tin (Galinstan, Ga ∼68.5 wt%, In ∼21.5 wt%, Sn ∼10 wt%, density: 6.44 kg/L) alloy and Gallium were purchased from Wochang (P. R. China). Carbonyl iron (iron pentacarbonyl, size ~2 μm) powder was purchased from BASF. Tween 80 was purchased from Aladdin. As water source deionized water (DI water) was used. The experimental materials were used as received without any further purification and treatment.