Investigation On Preparation Of Polypyrrole Com Posites And The Properties Of The Charge Storage In Microbial Fuel Cells

Microbial Fuel Cell(MFC)is a new kind of technology that can deal with organic pollutants in sewage and simultaneously produce electric energy.The performance of microbial fuel cell is determined by the microbial activity on the anode surface.Anode material of MFC played a very important role in microbial activity.In this paper,we prepared polypyrrole and its composite material,whose application as anode in MFC and influence in the electrical generation and energy storage performance of MFC.Carboxymethyl cellulose/polypyrrole composite electrode material doped with different mass fractions was prepared by in situ growth method.The optimal ratio of polypyrrole(PPy)and carboxymethyl cellulose(CMC)in composite materials was obtained by electrochemical test.And then PPy-CMC/S electrode was prepared.In our study,the maxinum power output of MFC with PPy-CMC/S electrode,PPy/S electrode,and S electrode as bioanode reached4.88 W/m~3,3.64 W/m~3,and 2.85 W/m~3,respectively.When the cell was charged for 60minuites and discharged for 120 minuites(C60/D120).The total electric(Q_m)produced by PPy-CMC/S electrode was 7000.43 mC/cm~2,compared with PPy/S anode and S anode,which improved by 2199.37 mC/cm~2 and 5814.25 mC/cm~2,respectively.In addition,the steady current obtained by PPy-CMC/S anode battery was 3.24 mA,which was 2.01 times(1.61 mA)and 5.31 times(1.61 mA)as big as PPy/S electrode and S electrode.PPy-CMC/CB electrodes and PPy-CMC-CNTs/CB electrodes were prepared by liquid-phase interface method.The prepared electrodes were electrochemically tested and used as anodes in MFC.The maximum power density of MFC equipped with PPy-CMC-CNTs/CB capacitive anode reached 13.20 W/m~3,which was 1.36 times and 4.43times as big as MFC equipped with PPy-CMC/CB electrode and blank carbon brush anode,respectively.The reproducibility test of MFC equipped with CB anode,PPy-CMC/CB anode and PPy-CMC-CNTs/CB anode were conducted for 5 cycles of charging 15 minutes and discharging 45 minutes(C15D45).It was found that the stable current of MFC equipped with PPy-CMC-CNTs/CB anode,PPy-CMC/CB anode,CB anode reached 1.73 mA,1.20 mA,and0.54 mA,respectively.The PPy-CMC-TiN/CB hydrogel electrode doped with different mass fractions of titanium nitride(TiN)was prepared by liquid phase interface method.The optimal doping ratio of titanium nitride was obtained by electrochemical test,and the electrode was used as an anode in MFC.The maximum power density of MFC equipped with PPy-CMC-TiN/CB capacitive anode reached 14.11 W/m~3,which was 1.45 times and 4.64 times as big as MFC equipped with PPy-CMC/CB electrode and CB electrode,respectively.The MFC was charged for 15 minutes and discharged for 45 minutes for 5 cycles.It was found that the MFC equipped with PPy-CMC-TiN/CB anode obtained steady currents of 1.49 mA,which was1.24 times(1.20mA)and 2.76 times(0.54)higher than the other two MFCs.