Effect Of Titanium Suboxide Electrode On Electricity Generation In Air Single-Chamber Microbial Fuel Cell

Microbial fuel cell(MFC)has drawn increasing attention as a promising technology for wastewater treatment and energy production.However,for the reasons of high cost and low power generation,the researches of MFC are still stuck in lab-scale.Aside from all the other factors affecting the MFC performance,including electrode material and inoculum,etc.,the fabrication materials of electrode play a profound role in influencing the power generation.Therefore,to explore a high-performance anode material is most essential to improve the power outputs of MFC.In this study,titanium suboxide(Ti4O7)was used as anode material of MFC and the polyaniline(PANI)/graphene composite modified Ti4O7 electrode was firstly prepared via constant potential method,and accounting for the need for producing new electrode materials for keeping on boosting microbial biovoltage in MFC.In addition,the modified electrode material after optimization,with oily wastewater as the target pollutant,was studied the performance and the degradation of pollutants of MFC under different conditions.The main contents of this paper are as follows.(1)The MFC reactor with titanium suboxide(Ti4O7)anode produced a peak power density of 361.9 mW/m2,which was 2.2 and 3.5 times of that with the carbon cloth and titanium sheet control.The cathode electrode was made of carbon cloth,without any catalyst.A peak current(Ipa)of 4.4 mA in the oxidation scan was observed at the titanium suboxide,which was 1.1 and 1.2 times of that with the carbon cloth and titanium sheet control.Higher Ipa indicate larger electrochemical active surface area.The charge-transfer resistance of titanium suboxide was 5.0?,and the charge transfer resistance is reduced by up to 21% and 63% comparing with the carbon fiber and titanium sheet control,respectively.A smaller charge-transfer resistance is resulted from a faster electron transfer rate.It indicates that the titanium dioxide is suitable as the anode material of MFC.(2)The PANI/graphene composite modified Ti4O7 electrode with high electrochemical activity was firstly prepared via constant 0.8 V,investigating the performance of modified electrode at different time and different concentration.The MFC reactor with PANI/graphene modified titanium suboxide(under the optimum modified condition)anode achieved the highest voltage with 980 mV,and produced a peak power density of 2073 mW/m2,which was 2.9 and 12.7 times of those with raw titanium suboxide control.A peak current(Ipa)of 7.5m A in the oxidation scan was observed at PANI/graphene modified titanium suboxide(under the optimum modified condition),which was 1.7 times of that with raw titanium suboxide control.Higher Ipa indicate larger electrochemical active surface area.The charge-transfer resistance of the PANI/graphene modified titanium suboxide(under the optimum modified condition)was 1.98?,and the charge transfer resistance is reduced by up to 60.4% comparing with raw titanium suboxide control.A smaller charge-transfer resistance is resulted from a faster electron transfer rate.The results show that the performance of microbial fuel cell has been improved after modification.(3)MiSeq sequencing method was used to analyse the microbial community structures of anolyte of MFC.The results showed that,the dominant phyla of anolyte were Proteobacteria(27.7%),Bacteroidetes(25.4%),Firmicutes(24.1%)and Lentisphaerae(15.3%),which became dominant members of electroactive communities.(4)The MFC reactor with PANI/graphene modified titanium suboxide anode and the cathode electrode was made of carbon cloth without any catalyst was used to degrade oil-containing wastewater,and was to explore the production of electricity of MFC under the conditions that of different COD,PH and COND.