Zirconium‑tin oxide interlayer modification enhances the performance and stability of the titanium-based lead dioxide...

In this study, a novel titanium/zirconium‑tin oxide/alpha‑lead dioxide/beta‑lead dioxide (Ti/Zr-SnO₂/α-PbO₂/β-PbO₂) electrode was prepared and utilized for degrading alizarin yellow R (AYR) dye. The Integration of impregnation drying, drop coating with a solvent, and high-temperature pyrolysis significantly diminished the characteristic fissure morphology of conventional pyrolytic metal oxide interlayers, thereby modulating the electrodeposition process of alpha‑lead dioxide (α-PbO₂) and enhancing electrode stability and electrochemical performance. Electrode characterization revealed that the charge transfer resistance (R_ct) was 88.0 Ω/cm², and the oxygen evolution potential (OEP, vs. Ag/AgCl) was 2.02 V. The electrochemically active surface area was the largest, with an accelerated lifetime of up to 82.37 h. That was 13.18 times longer than that of the Ti/α-PbO₂/β-PbO₂ electrode (6.25 h) and 8.83 times longer than that of the Ti/Zr-SnO₂/β-PbO₂ electrode (9.33 h). Under optimal experimental conditions (400 A/m², 50 mg/L, 20 °C, pH = 8.00), the removal rate of AYR by this electrode was 99.90 %, the chemical oxygen demand (COD) removal rate was 74.64 %, the average current efficiency (ACE) was 50.94 %, and the electric energy per order (E_EO) was 41.17 kWh/m³. The AYR degradation process followed to a quasi-zero-order kinetic model (k = 0.2745 min^-1). In the real water treatment, AYR and COD removal rates remained above 90.13 % and 62.57 %, respectively. This study demonstrated that the Ti/Zr-SnO₂/α-PbO₂/β-PbO₂ electrode significantly improved electrocatalytic performance and stability through the unique preparation of its interlayer, exhibiting great potential for efficient dye wastewater treatment.