화학공학소재연구정보센터
Journal of Applied Electrochemistry, Vol.49, No.4, 369-377, 2019
Eco-friendly and facile electrochemical synthesis of sub-micrometer lead powders in deep eutectic solvents using galena as a raw material
The sub-micrometer lead powders were electrodeposited on a mild steel (MS) substrate in PbS-containing (10-50mM) choline chloride-urea deep eutectic solvent (ChCl-urea DES) at 353K and 2.5V. The electrochemical behaviors of the Pb(II)/Pb on MS and glass carbon electrodes were determined by cyclic voltammetry and chronoamperometry measurement. It indicates that the reduction of Pb(II) is a quasi-reversible process. The increase in PbS concentration effectively promotes the E-Pb(II)/Pb shift in positive direction which can facilitate the reduction of Pb(II). The initial nucleation stage of metallic lead on MS electrode is a three-dimensional instantaneous nucleation for diffusion control and the diffusion coefficient of Pb(II) at 353K is about 2.40x10(-7)cm(2)/s. The three-dimensional sub-micrometer lead particles are agglomerated together and composed of many overlapped lead flakes about 150-200nm. Moreover, the XRD results reveal that metallic lead can be deposited with a face-centered-cubic structure and the strongest peak intensity is (111) plane. This finding provides a theoretical guidance for the one-step preparation of sub-micrometer lead powders using galena concentrate as raw material by an eco-friendly and facile electrochemical approach in close neutral electrolyte, which can efficiently shorten the production flow and realize the integration of metallurgy and material processes. [GRAPHICS] .