Research On The Preparation Of SnO₂/Fe₃O₄ Particle Electrode And Electro-Catalytic Performance Of Three-dimensional Electrode System

The electrocatalytic performance of three-dimensional electrode system based SnO₂/Fe₃O₄ particle electrode,the three-dimensional electrode influence factors,dynamics and the mechanism of wastewater treatment will be studied through the degradation of RhB.The Ti/SnO₂-Sb₂O₅ anode plate was prepared by Ti plate coating.The different proportion of SnO₂/Fe₃O₄ particle electrodes with good magnetic properties were prepared by a hydrothermal method.The characterization of Ti/SnO₂-Sb₂O₅ and SnO₂/Fe₃O₄ were characterized by means of XRD,SEM,TEM,BET,XPS and VSM.Results showed that Ti/SnO₂-Sb₂O₅ produced a strong and tight coating on the surface,increasing the contact area with the organic matter.The catalytic layer of as-prepared particle electrodes had stable load,good conduction and was easy to recycle and reuse,which were beneficial for the electrocatalytic reaction.The electrocatalytic property was investigated by electrochemical workstation.Cyclic voltammetry curves show that the initial oxygen evolution potential is 2.1V.The oxygen evolution current of three-dimensional electrode on degradation of RhB was higher than that of the other electrode system.LSV shows that particle electrode has higher conductivity and EIS shows particle electrode has a lower resistance,which is beneficial to the transfer of the electron in electrocatalysis.The results showed that when molar ratio of the SnO₂ and Fe₃O₄ is 1:1,the electrocatalytic performance of the particle electrode is the best.The removal ratio of RhB and TOC were 100%and 83%in 90 min,respectively.Comparison of different electrode system for RhB wastewater degradation can be obtained.In terms of the degradation rate of RhB and TOC,the effect of particle electrode adsorption are less than10%,and two-dimensional electrode is 48%and 43%.In the three-dimensional electrode system,the degradation rate of RhB and TOC removal rate were 77%and 68%,when Fe₃O₄was the particle electrode.When SnO₂/Fe₃O₄ was used as the particle electrode,the degradation rate of RhB and the removal rate of TOC were 100%and 83%.The removal ratio of 20mg/L RhB wastewater was 100%with electrocatalytic time of90min,electrolyte concentration of 0.1mol/L,electrolyzer voltage of 40v,pH of 3 and SnO₂/Fe₃O₄ dosage of 0.75g/L.The removal ratio of RhB and TOC were still above 93%and 77%,respectively,after particle electrode were reused 5 times,which had still a excellent and stable electrocatalytic performance.In the reaction,the degradation kinetics of RhB is a first-order kinetic model.The study on degradation mechanism of wastewater show direct oxidation of anode has obvious effect,and in three-dimensional electrode system particle electrode is the main reaction.After the addition of·OH capture agent tert butanol,the degradation rate of RhB decreased by 64%and the removal rate of TOC decreased by 51%.The·OH is the main activity of the degradation of organic compounds.