Layered PbO2 electrode decorated with Ni-doped Mn5O8 peach-like microspheres for reinforced acidic oxygen evolution reaction in zinc electrowinning

Developing anodic electrocatalysts with superior activity and durability suitable for acidic oxygen evolution reaction (OER) remains a challenge to overcome. Herein, a layered Pb-(0.76 wt%)Ag/α-PbO2/β-PbO2 electrode modified with Ni-doped Mn5O8 particles (PA/PbO2-NMO) is successfully synthesized by a coprecipitation coupling with anodic codeposition process. The physical characterization demonstrated that the surface of electrode is composed by β-PbO2 and portion NMO that embedded in the deposit. In addition, it presents a layer structure, in which PA serving as support, α-PbO2 as the mid layer enforcing the adherence, and β-PbO2-NMO function as active layer. Benefiting from the above unique layered structure, the as-fabricated PA/PbO2-NMO electrode with a layered structure exhibits the outstanding acidic OER performance (583 mV, 139.04 mV dec–1) at 50 mA cm−2 in 1.53 M H2SO4. Meanwhile, the responding accelerated corrosion life at 1.5 A cm−2 is up to 64 h, indicating its robust anticorrosion ability. As for the applied performance in zinc electrowinning simulation electrolyte (1.53 M H2SO4 + 0.31 M ZnSO4), the current efficiency of the PA/PbO2 electrode is promoted to 93.8 % after the modification with NMO. Moreover, the cell voltage and one-ton zinc energy consumption of the modified PA/PbO2 electrode are diminished by 14.32 %, 17.75 % compared with the industrial Pb-(0.76 wt%) Ag (PA) electrode. Therefore, this study offers a new horizon on the development of the anodic electrocatalyst for both strongly acidic watersplitting and non-ferrous metals electrowinning.