Preparation of La-doped Ti/SnO2-Sb2O4 anode and its electrochemical oxidation performance of rhodamine B.

Abstract

In this paper, La-doped Ti/SnO2-Sb2O4 electrode was prepared by electrodeposition and used for electrochemical degradation of rhodamine B. The optimum preparation conditions of the electrode were optimized as deposition time of 15min and calcination at 500 ℃ for 2h. The water treatment conditions were selected as initial pH 3.0, electrolyte Na2SO4 concentration 0.1M, current density 30mAcm-2, and initial rhodamine B concentration 20mg L-1; the color and TOC removal of RhB reached 99.78% and 82.41% within 30min. The FESEM, XRD, XPS, CV, LSV, and EIS characterization studies demonstrated that Ti/SnO2-Sb2O4-1%La electrode had a dense structure and the highest oxygen evolution potential (2.14V) and lowest charge transfer resistance (0.198 Ω cm-2), indicating that doped La has lower energy consumption. Moreover, La doping can expand the specific surface area, active site, performance of pollutant degradation, and service life of the electrode. Especially, the service life of Ti/SnO2-Sb2O4-1%La is increased by three times, and the maximum life span reaches 90min (1000mAcm-2, 1M H2SO4). Free radical quenching experiments show that ·OH plays a major role in the degradation of RhB. The Ti/SnO2-Sb2O4-1%La electrode prepared in this paper and its results will provide data support and reference for the design of efficient electrocatalytic electrode.