Preparation And Electrocatalytic Performance Studies Of MnO_x-matrix Composite Electrode By Electrochemical Anodic Co-deposition Method

Over the past century has water pollution been attracting the attention of governments,organizations and people throughout the world,thus has become one of the most urgent problems.Among plenty of wasterwater treatment technologies,advanced electrocatalytic oxidation process,as one of environmentally friendly water treatment processes,has been coming into hot spot in current research,due to its high efficiency and no second pollution for wastewater treatment.This thesis is mainly focused on the preparation and modification of Ti/MnOx electrodes.Thereinto,the effects of composite co-deposition and co-electrodeposition are investigated deeply.The experimental factors of the anodic electrodeposition were studied to prepare Ti/MnOx electrodes.The catalytic properties and active layer composition of electrodes were investigated through the polarization curve and electrochemical impedance spectroscopy(EIS),and X-ray diffraction(XRD).With the investigation of experimental conditions,the optimized preparation condition was a 5mA·cm-2 current density,70 ? deposition temperature,0.25mol-L-1 electrolyte concentration and 3 pH value.In the optimized preparation condition,smooth and dense electrodes were obtained.The removal efficiency of phenol on the Ti/MnOx electrode was 53.2%.Because of the fact that the small size effect of nano materials can reduce the disadvantage of single material and enhance some properties of material,Ti/MnOx electrodes were modified through compositing rare earth oxide nanoparticles,enhancing the active layer compactness and increasing the accelerated service lifetime.The degradation efficiency of phenol on the electrode with the optimal composite amounts of 0.08g/250mL nano-CeO2 was 75.34%,while it was 82.46%with the optimal composite amounts of 0.04g/250mL nano-La-2O3.Anodic co-electrodeposition was applied to prepare lead manganese mixed oxide electrodes to overcome MnO2 disadvantage of low oxygen evolution potential and poor stability.The experimental results show that the phenol degradation efficiency and accelerated service life were advanced significantly.In the optimized co-deposition condition of 10mA·cm-2 current density,50 ? deposition temperature,and 3/8 lead and manganese ion concentration proportion,the accelerated lifetime of mixed oxide electrode was 3366s,increasing by 10.58 times.Meanwhile,the phenol degradation efficiency was 88.42%.