Fabrication of a highly active β-PbO2-Co3O4 electrode for zinc electrowinning by pulse electrodeposition: Characterization and catalytic performance analysis

High oxygen evolution overpotential and low corrosion resistance are regarded as the main drawbacks of anode materials in zinc electrowinning . To improve the electrocatalytic activity of oxygen evolution reactions (OER) and reduce energy consumption in zinc electrowinning, a Co 3 O 4 nanoparticle-modified PbO 2 anode was prepared on a Ti substrate with Sn-SbO X as an interlayer through pulse electrodeposition . The surface morphology, phase composition, and electrochemical properties of the as-prepared anode were systematically investigated. The introduction of Co 3 O 4 nanoparticles refined the crystal size of PbO 2 and increased the surface roughness of the anode. Electrochemical tests suggested the excellent electrocatalytic activity of the Co 3 O 4 nanoparticle-modified PbO 2 anode. Density functional theory (DFT) calculations revealed that Co 3 O 4 nanoparticles reduced the OER free energy (1.58 eV) and that pulse electrodeposition reduced the PbO 2 crystal size and increased the active surface area of the anode. In the simulated zinc electrowinning test, an improved current efficiency (90.6 %) was achieved, and the low energy consumption (2,508.29 kW·h) for zinc production per ton was significantly reduced as compared with that for the conventional Pb-0.75 %Ag anode. The lifetime of the modified electrode is increased by approximately 36.8 %. This provides a reference for the design and development of anode materials with high oxygen evolution activity and strong corrosion resistance in zinc electrowinning systems.