Improved Electrocatalytic Degradation of Alizarin Yellow R by Ti/Zr-SnO2/PbO2 Electrodes Doped with Ytterbium

Abstract

Introduction: Electrochemical oxidation of Alizarin Yellow R (AYR) was investigated on Ytterbium (Yb) doped Ti/PbO2 electrodes prepared by an electrodeposition method. Method: The etching of the Ti sheet by using a mixed acid of H2SO4 and TA (volume ratio= 2: 1) for 50 min at 100 °C could produce a suitable interface for further modification. The morphologies, composition, and electrochemical properties of Yb doping on the electrode were characterized by SEM (Scanning Electron Microscopy), EDS (Energy-Dispersive Spectroscopy), Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The introduction of an appropriate intermediate layer, Zr-SnO2, was performed. We also tried to fabricate Ytterbium (Yb) doped Ti/Zr-SnO2/PbO2 electrodes by an electrodeposition method on the intermediate layer of Zr-SnO2. The surface morphology of the Ti/Zr-SnO2/PbO2 electrode was changed due to the Yb doping, which affected the electrocatalytic activity of the modified electrode. Result: The developed Yb-doped Ti/Zr-SnO2/PbO2 electrode showed improved removal efficiencies toward AYR. Conclusion: The effects of current density and initial AYR concentration on the electrochemical oxidation of AYR by Yb-doped Ti/Zr-SnO2/PbO2 were investigated. The removal rate of AYR was 97.3% in 180 min under the conditions of the current density of 60 mA/cm2 , initial AYR concentration of 50.0 mg L-1 , and Na2SO4 concentration of 0.10 mol L-1 .