Enhancing electrocatalytic performance for SnO2-Sb, Ni coatings induced by high-resistance layer and surface active layer in combination with alternating thick/thin layer method

Abstract

Developing an electrochemical degradation system with high catalytic efficiency and extended operational lifetime is crucial for practical industrial applications. In this study, a novel Sb, Ni-doped tin oxide-coated electrode, named A@SnO₂-Sb-Ni/SnO₂-Sb/Ti, featuring a high-resistance intermediate layer (HRIL) and surface active layer in combination with alternating thick and thin layers (ATTL) method was proposed to enhance both catalytic performance and stability. The potential divider effect of the SnO₂-Sb HRIL and fine cracks on the surface induced by alternating thick and thin active layer not only effectively reduce the dissolution rate of the active layer but also inhibit the direct dissipation of the Ti substrate by the electrolyte, which collaboratively increases the overall stability of the electrode. Accelerated life test results demonstrated that the stability of the A@SnO₂-Sb-Ni/SnO₂-Sb/Ti electrode showed a 110 % improvement in acidic environments compared to the traditional SnO₂-Sb-Ni/Ti electrode. At a constant current density of 10 mA cm⁻² applied to a 4.0 cm² electrode, nearly complete degradation of Rhodamine B (100 mL, 20 mg L⁻¹) was achieved within 15 min.