Study Of Titanium Based Sn-Sb Oxides Coating Anodes

The average gross occupancy volume of water resource in our country is very poor, and the water resource was seriously polluted, the pollution of the water resource may become one of the important factors that restricts the development of our country. The electrochemical oxidative destruction of toxic and biologically refractory organic pollutants in water is a prospect method, but it is restricted by the electrode materials. It is exactly the key to solving this problem to develop the high oxygen overvoltage anodes of good properties. In this paper we aim at the research and development circumstance, carry on systematic research based on the tin and antimony oxide electrode and some coating modifying study. The purpose is preparing high oxygen overvoltage anodes with choiceness properties.In this thesis, we first do the study of preparing Ti/SnO₂-Sb₂O₅ anode by thermal decomposition method. The preparing temperature chosen is 600℃, 550℃, 500℃, and the mol-proportion of tin and antimony chosen is 5:1, 9:1, 20:1,30:1,40:1,50:1, 100:1.The result is that:(1) The Ti/SnO₂-Sb₂O₅ anode prepared in the condition of 550℃ and 9:1 has the best stability and its service life is the longest.(2) XRD indicates the crystal structure of electrodes prepared under all conditions were all rutile, and the crystal structure of electrode's surface have no large change after the strengthening electrolysis.(3) The voltammetric charge and the porosity that plotted by electrochemistry method was related the property of the coating of the electrode's surface.(4) SEM indicates, the surface structure of electrodes appears " mud " structure, and surface coatings obviously fall off after strengtheningelectrolysis experiment, The structure is one of the important reasons that effects the stability of the electrode.(5) It is very small that Electron transfer ability of the electrode is influenced by content of antimony.(6) The electrolysis experiment of degraded phenol and aniline indicates that the Ti/SnOi-SbiOs electrode prepared under the optimum condition can totally degrade the organic pollutants in the solution;(7) We found the optimum condition of thermal decomposition that temperature is 550°C, the Sn:Sb(mol) is 9:1, The electrode prepared under this condition had the better electron-transfer ability, and the longest strengthening service life, and some electro-catalytic activity to organic contaminants.In this thesis, We went on modifying research through intermingling the third element and adding interlayer. We prepared Ti/SnO2-Sb2O5-MnO2, Ti/SnO2-Sb2O5-LaO2, Ti/SnO2-Sb2O5-CoO2, Ti/SnO2-Sb2O5-RuO2, Ti/SnO2-Sb2C>5-Ir02 anodes which mol-propotion is 9:1:1, and the Ti /IrO2/SnO2-Sb2O5, Ti /RuO2/SnO2-Sb2O5 anodes with 1.5mg/cm2 RuO2 and IrO2 oxide interlayer.The results as follows:(1) Service life of the electrode that intermingled manganese element got longer, but its oxide coating dissolved in the process of strengthening electrolysis. This indicated that the Ti/SnO2-Sb2O5-MnO2 electrode was instable, and the consuming of the coating was the reason that the electrode lost activity. The service life of the Ti/SnO2 — Sb2O5 — LaO2 electrode and Ti/SnO2^Sb2C>5 —CoC>2electrode was too short.(2) Intermingling noble element iridium is propitious to prolong the service life. Intermingling ruthenium element can not prolong the service life.(3) The Ti/SnO2-Sb2O5-MnO2 , Ti/SnO2-Sb2O5-CoO2 and Ti/SnO2-Sb2O5-IrO2 almost have no electro-catalytic oxidative activity to organic contaminants.(4) The Ti/SnO2^Sb2Os — LaO2 electrode has response to all the organic...