Preparation and Characterization of a Pd modified Ti/SnO2-Sb anode and its electrochemical degradation of Ni-EDTA

An optimized metal oxide electrode (Ti/SnO2-Sb-Pd) was prepared via thermal decomposition and used in the electrochemical degradation of Ni-EDTA. The electrode was characterized by SEM, XRD, XPS, and electrochemical characterizations including linear-sweep voltammetry (LSV), cyclic voltammetry (CV) and chronopotentiometry (CP) techniques. It was found that Pd doping could effectively change the surface morphology and lattice parameters of the metal oxide electrode. Pd can facilitate the entry of more Sb into SnO2 crystals and promote the reduction of Sb from the +5 to the +3 state. The interaction of these metals raised the oxygen evolution potential (OEP) and electrochemical surface area of the electrode, in addition to reducing the degradation potential and increasing the degradation current of NiEDTA. When the molar ratio of Pd: Sn was 2.5%, the electrode could simultaneously degrade 87.5% of NiEDTA and recycle 17.9% of elemental Ni on the cathode within 120 min. At the same time, with Pd doping, the lifetime of the electrode was increased more than 40 times, demonstrating good potential for application in industry. (C) 2017 Elsevier Ltd. All rights reserved.