Preparation And Application Of Cathode Catalyst For Photoelectrocatalytic Process

Since the discovery of the photocatalytic character of TiO₂ in 1972, numerous investigations have been made on its application for the chemical conversion of light energy,the photocatalytic treatments of organic compounds,photochemical synthesis,the synthesis of self-cleaning material.Particularly,TiO₂ photocatalyst is highly emphasized in the degradation of organic compounds.In order to improve the degradation efficiency of photocatalyst,electricity is applied to the degradation experiment of organic compounds with TiO₂ photocatalyst and achieves good result which makes photoelectrocatalytic degradation of organic compounds be put forward.Besides,there are numerous studies on anode,but few studies on cathode and cathode catalyst.According to photoelectrocatalytic reaction theory of semiconductor anode and gas cathode,the holes and-OH generated on the two poles can completely degrade organic contaminates,and finally produce CO₂,H₂O and clean inorganic constituents.Therefore,for further enhancing efficiency of the degradation under photoelectrocataliyic condition,this thesis,which includs three parts,mainly studied the preparation,application and Characterization of Cathode Catalyst.In the first part,preparation and Characterization of Pt/C Cathode Catalyst were investigated.Pt/C catalysts were prepared by impregnation method,using XRD,TEM,SEM technology for characterizing crystal structure,size,distribution and surface macrograph of Pt/C catalyst.In order to clarify the effects of different preparative conditions of catalysts on the catalytic activity of Pt/C catalyst,a series of experiments on degradation of phenol were conducted.The results show that 1.0%wt Pt /C catalyst provided the favorite catalytic activity during the degradation of phenol,which is prepared under the conditions of 70℃,0.3g stabilizing agent,9mL formaldehyde and pH=7,and the Pt metal particles in the Pt/C catalyst are homogeneously dispersed,the average diameter of Pt particle is 5.0nm.In the second part,preparation and Characterization of Pd/C and Pt-Pd/C Cathode Catalyst were studied.Crystal structure and surface macrograph was characterized by XRD,SEM technology.The catalytic activities of different content Pd/C,same content Pd/C and Pt/C,different content Pt-Pd/C catalyst were compared during the degradation of phenol, which were prepared under the same conditions.The results showed that 1.0wt%Pd/C and(1.0wt%Pt-1.0wt%Pd)/C catalyst provided the favorite catalytic activity,Pt/C catalytic activity is always better than Pd/C. In the last part,we have studied the application of Pt/C gas cathode during the degradation of phenol.In order to clarify the effects of degradation of phenol under different experimental conditions,a series of experiments were conducted.The experimental results showed that the effects of degradation of phenol is better during the photoelectrocatalytic reaction process,which is based on the following experimental conditions:1.0wt%Pt/C gas cathode,adding -2.0V,different pH value, through atmosphere,100%phenol concentration was degraded within 80 min,and the removal rate of TOC was reached 87.0%after 2.0h reaction.My experimental results showed that Pt/C gas cathode can quickly enhance the degradation rate and mineralization of phenol during the photoelectrocatalytic reaction process,which shows cathode catalyst has a promising prospect on degradation of organic compounds during the photoelectrocatalytic process...