Abstract
At present time, semiconductive thin films used in photovoltaic cells can be successfully electrodeposited using ionic liquids in lab scale. However, scaling-up of this technology is hazardous due to the complexity involved to conduct electrodeposition in inert gas atmosphere. This paper reports on a novel approach for electrodeposition of gallium from a chloroaluminate ionic liquid composed of anhydrous aluminum chloride (AlCl3) and 1-ethyl-3-methylimidazolium chloride (EMIC) in ambient atmosphere, after protection with a non-water-absorbable hydrocarbon layer. Cyclic voltammetry (CV) measurements were undertaken to characterize the electrodissolution and electrodeposition behavior of Ga. Potentiostatic electrodeposition experiments were conducted to deposit functional Ga layers on platinum, nickel, and mild steel substrates. SEM/EDX investigations revealed that Ga deposits have inhomogeneous microstructure developed through the progressive nucleation-growth mechanism that has been controlled by diffusion of Ga cations.
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•Ga was electrodissolved and electrodeposited in a chloroaluminate ionic liquid.•Covering ionic liquid with decane layer facilitated electrodeposition of Ga in air.•The approach may facilitate scaling-up electrodeposition of semiconductors.