Study On Preparation And Catalytic Performance Of Ti/SnO₂ Electrode Modified By Graphene Doped With S

Electrochemical oxidation as an environment-friendly technology has been widely favored by researchers.As the core of electrochemical oxidation,its performance directly determines the effect of the electric oxidation system.Ti/Sb-SnO₂ electrode material stands out because of its high oxygen evolution potential and strong electrocatalytic activity,etc.,and has been recognized by researchers.However,it also has fatal defects,modification by doping is an effective way to improve the performance of the electrode.In this paper,in order to further improve the stability and service life of Ti/Sb-SnO₂ electrode,on the basis of the use of Ce-Mn intermediate layer and active layer doped rare earth element La,wire mesh titanium was selected as the matrix,and S-doped graphene oxide was introduced into the active layer.The electrode was tested by SEM,XRD,XPS and Raman.The electrochemical performance,electrocatalytic performance and accelerated life of the electrode were also measured.The experimental results show that compared with the wire mesh Ti/Ce-Mn/SnO₂-Sb-La electrode,the electrode prepared by introducing S doped GO into the active layer has a denser surface,showing a sense of three-dimensional intersecting.The crystallization degree of SnO₂ is significantly improved,and its electrocatalytic performance is more excellent.The oxygen evolution potential increased from 1.78 V to 2.12 V,with a lower reaction resistance of 62.03Ω·cm²,and a oxide film resistance of 3.91Ω·cm².In the experiment of phenol degradation for 2 h,the removal rate of phenol and COD was 89.5%and 79.8%respectively for the electrode prepared by introducing S doped GO into the active layer.The enhanced accelerated life experiments show that,compared with the wire mesh Ti/Ce-Mn/SnO₂-Sb-La electrode,the accelerated life of the active layer with the introduction of S doped GO is 1.5 times that of the wire mesh Ti/Ce-Mn/SnO₂-Sb-La electrode,and the maximum accelerated life can reach 2.73 h.The introduction of S doped GO in the active layer can improve the stability and service life of the electrode.In order to further improve the catalytic oxidation effect of the electric oxidation system on pollutants,on the basis of conventional electrocatalysis,magnetic Fe₃O₄nano-spheres were prepared by solvothermal reduction method and their surfaces were modified,a dynamic electrooxidation system was built on the basis of conventional electrocatalysis,and the influence of different factors on the removal efficiency of phenol by dynamic electrooxidation was explored,and the optimal conditions were determined.The efficiency differences of degradation of phenol wastewater by dynamic electrooxidation and conventional electrooxidation meters were compared before and after adding magnetic microspheres,the mechanism of dynamic electrooxidation was revealed,which provided a theoretical and research basis for the application of magnetic nanoparticles in water treatment.The optimal conditions:current density of 10 m A/cm²,magnetic particle dosage of 4 g/L,Na₂SO₄concentration of 0.25 mol/L,plate spacing between cathode and anode of 2 cm,magnetic separation time of 2 min.Under the optimum conditions,the removal rate of phenol wastewater by dynamic electrooxidation and conventional electrooxidation with magnetic microspheres was compared.The efficiency of electrocatalytic degradation of phenol at 60 min by dynamic electrooxidation was as high as that at 120min by conventional electrooxidation.The addition of magnetic nano-spheres effectively improved the efficiency of electrocatalytic degradation of phenol.