fig3

Figure 3. Electrochemical and morphological evaluation of surface-regulated Sn electrodes. (A) LSV curves and (B) Tafel plots of Sn foils treated for different durations; (C) Optical photographs and (D) voltage-time profiles of symmetric cells based on different Sn electrodes at a current density of 5 mA mg^-1; (E) Voltage-time profiles of Sn-based symmetric cells at 0.1 mA cm^-2 with or without PbSO₄ additive; Post-cycling SEM images of (F) pure Sn, (G) pure Sn + 0.001 M PbSO₄, (H) the 4 h-treated Sn electrode, and (I) the 4 h-treated Sn electrode + 0.001 M PbSO₄. SEM: Scanning electron microscopy; LSV: linear sweep voltammetry.