Preparation And Properties Of Gd-doped Tin-antimony Electrodes By Electrodeposition And Sol-gel Methods

Electrocatalytic oxidation is more and more widely used in the field of sewage treatment because of its high efficiency,environmental friendliness,simple operation,low energy consumption,thorough degradation and certain selectivity.The role of electrode materials in electrocatalytic oxidation technology is very critical.How to develop an electrode material with simple preparation,high catalytic efficiency and good stability is a very necessary subject.In recent years,tin-antimony electrodes have attracted the attention of researchers because theeir good catalytic performance and high oxygen evolution potentialtheir at a low price.However,titanium-based tin-antimony electrodes also have problems of low degradation efficiency and short service life.Therefore,improved preparation methods and further modification are required in order to promote the application of titanium-based tin-antimony electrodes.In this work,titanium dioxide nanotubes(TiO2-NTs)were prepared on titanium substrate by anodizing method and used as the base material of tin-antimony electrode,and then SnO2-Sb film layer was prepared by a combination of electrodeposition method and sol-gel method.In order to improve the electrochemical performance and catalytic performance of the electrode,the electrodes were optimized and improved in the following three aspects in this work.Relevant electrochemical tests and morphological characterizations were carried out.The main results are:(1)The process conditions of electrodeposition and sol-gel preparation of SnO2-Sb film on TiO2-NTs substrate obtained by anodization were optimized.The TiO2-NTs/SnO2-Sb electrode prepared by dipping five times in the sol-gel solution has better performance,the removal rate of phenol within 2 h reaches 76.95%,and the service life is predicted to reach 4200 h.(2)The Ag-TiO2-NTs/SnO2-Sb electrode was prepared by doping Ag on the TiO2-NTs substrate by electrodeposition.The catalytic degradation efficiency of phenol was increased from 76.95%to 87.88%,and the electrode stability was improved,the predicted service life is extended from 4200 h to 6300 h.(3)The Gd-TiO2-NTs/SnO2-Sb electrode prepared by doping the TiO2-NTs substrate with Gd element by the dipping method has a phenol removal rate of 92.64%and a predicted service life of 11500 h.The performance of the Gd-TiO2-NTs/SnO2-Sb electrode is better than that of the Ag-TiO2-NTs/SnO2-Sb electrode,which greatly improves the overall performance of the electrode.(4)The Gd-TiO2-NTs/SnO2-Sb-Gd electrode prepared by using Gd-TiO2-NTs as the substrate and doped with Gd element in the outer SnO2-Sb film layer has an oxygen evolution potential of 2.19 V,the removal rate of phenol can reach 96.19%within 2 h,and the predicted service life can reach 16300 h.The catalytic performance and service life of the electrode were further improved by doping and modification of Gd element in the film layer.