The Experimental Study On The Replacement Of Nafion By The Cathode Of Microbial Fuel Cell Cathode With PVDF

In this paper,a single-chamber air cathode-microbial fuel cell?MFC?reaction system was used as the research object,and the MFC cathode was used to replace Perfluorosulfonic acid-PTFE copolymer?Nafion?as the adhesive by means of polyvinylidene fluoride?PVDF?.By linear volt-ampere scanning method?LSV?,infrared spectrum?FTIR?,X-ray diffraction?XRD?,scanning electron microscope?SEM?characterization methods,such as power density of MFC,potential,COD removal and coulomb efficiency?CE?were analyzed,and the parameters such as compared the two kinds ofpolytetrafluoroethylene?PTFE?and PVDF binder performance of cathode,the cathode performance of different concentration of PVDF binder and the influence factors in the research of the system,and the research results show that:The properties of MFC production of two different adhesives,PTFE and PVDF,were investigated.Air cathode conductive properties of two kinds of adhesive is almost the same,but from the most high power density,COD removal and coulomb efficiency characterization result,PVDF do air cathode adhesive MFC,has a better performance and battery cathode production performance,so the PVDF can be a better MFC adhesive substitutes.PTFE do air cathode adhesive must be high temperature sintering processing?340??,can achieve the waterproof after PTFE contraction and the function of the air.PVDF,by means of phase transformation in the water does not need high temperature treatment,can promote the protons and oxygen in the catalytic layer,for the purpose of oxygen reduction reaction,to a certain extent,save the use of energy.According to the power density curve,the maximum power density obtained by the MFC of PVDF is 1586 mW·m^-2,which is higher than the 1146 mW·m^-2 produced by the MFC of PTFE.The COD removal rate of the MFC of PTFE is up to 67.94%,and the MFC removal rate of PVDF is up to 78.33%.The MFC of two kinds of air cathode binder has good removal effect on COD.The MFC coulomb efficiency of PTFE is up to 87.46%,and the MFC coulomb efficiency of PVDF can be up to 89.97%.PVDF is used as a binder for more organic matter in MFC to participate in aerobic reactions.In the same MFC system,the air cathode performance of PVDF adhesives with different concentrations was investigated.MFC air cathode based on PVDF binder,activated carbon and the ratio of PVDF is the best value,levels of raw materials in the catalyst layer and diffusion layer is activated carbon/PVDF=3:1 and conductive carbon black/PVDF=1:1,PVDF do adhesive air cathode MFC maximum power density of 1586 mW·m^-2.Four PVDF concentrations of air cathode MFC,10%PVDF have the highest COD removal rate.No matter which concentration of MFC,CE changes show commonality.The higher the resistance value,the lower the current density,and the lower the corresponding CE.However,the CE does not increase with the increase of current density,and the instability of the internal resistance leads to the instability of the voltage output,which leads to the decrease and increase of CE.At the same time,using the XRD,infrared test and other characterization methods,the higher the concentration of PVDF in the air cathode,the better the catalytic oxygen reduction.Use PVDF binder in the study of the influence factors of proof:the battery,in the process of start domesticated,but at the same time,only replacement and supplement nutrition,the mixture of MFC than inoculation fluid replacement and nutrition,the mixture ratio of 1:1?v/v?of MFC startup faster and highest voltage stability;Sodium acetate is more suitable for MFC substrate;MFC more than 20? environment temperature is suitable for the environmental temperature 30?.