Preparation of sub-micrometer lead wires from PbO by electrodeposition in choline chloride-urea deep eutectic solvent

• Sub-micrometer lead wires were prepared by electrodeposition in PbO–ChCl-urea DES.
• Cyclic voltammetry demonstrated that Pb(II) can be reduced to metallic state.
• Raising temperature results in the particle size of lead wires increasing.
• The refinement of lead wires is observed with the increasing of current density.
• Lead wires have a mean size of 2–4 μm in length and 1 μm in diameter at 323 K.

The sub-micrometer lead wires have been prepared by lead electrodeposition onto a stainless steel substrate from 40 mM PbO + choline chloride-urea deep eutectic solvent. The electrochemical behavior of the PbO dissolved in this solvent was investigated with cyclic voltammetry. It is demonstrated that a substantial overpotential is required to initiate the lead deposition process on the stainless steel substrate because a nucleation loop is generated. Temperature and current density have obvious effect on the cathodic current efficiency, specific energy consumption, and deposits morphology during the lead electrodeposition. The highest current efficiency (96.45%) and the corresponding specific energy consumption (649.10 kW h t−1) were achieved at 130 A m−2 and 343 K. The lead wires obtained at 323 K have a mean particle size of 2–4 μm in length and 1 μm in diameter. The XRD patterns of the deposits indicate that purified lead is obtained with face-centered cubic crystal structure and the crystallites are predominately oriented in (2 0 0) plane.