Effects of cyclic voltammetric scan rates, scan time, temperatures and carbon addition on sulphation of Pb disc electrodes in aqueous H₂SO₄

Abstract

Herein, we aim to specifying effects of cyclic voltammetric scan rates, scan time, temperatures and carbon addition on electrochemical sulfation of lead disk electrodes. Electrochemical transformation between solid Pb and solid PbSO 4 was investigated by cyclic voltammetries (CVs) of Pb disk electrodes in aqueous H 2 SO 4 , in line with the morphology change of electrodes before and after CV polarizations. Too rapid or slow scan rates tend to cause more irreversible sulfation. Long-duration cycling inevitably causes loss of active layer on the electrode surface and incurs more irreversible sulfation. Sulfation becomes more efficient and reversible at elevated temperature. Reversibility of sulfation of lead gets enhanced with formation of more uniform and less crystalline particles. The irreversible sulfation became less with addition of carbons (CNT or AB) in the electrolyte, due to lower polarizations upon carbon addition. The protocol of carbon addition is more effective at initial stage of cycling and becomes less effective at later stages. It is acknowledged that the improvement on long-term cycling remains a challenge, yet, which deserves further study.

Influence of the electrochemical processing parameters on the photocurrent–voltage conversion characteristics of copper bismuth selenide photoactive films

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Hexaferrocenium tri[hexa(isothiocyanato)iron(III)] trihydroxonium complex as a new DNA intercalator for electrochemical DNA biosensor

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Investigation of anodic dissolution behaviour of intermetallic compound in Sn-3Ag-0.5Cu solder alloy by cyclic voltammetry

“…As the scan rate decreased from 1.00 mVs −1 to 0.05 mVs −1 , the peak potential had shifted from −0.20 V to −0.23 V, while the peak current had significantly reduced from 13 mA to 4 mA. The shifting of the peak potential and the reduction of its current had suggested a lower polarization effect at a lower scan rate (Zhu et al , 2016). Thus, it is more suitable to study the dissolution behaviour using a lower scan rate due to the minimized polarization effect.…”