Research On Polyaniline/chitosan Composite Materials And Their Influence As Anode Towards Power Production Capacity And Charge Storage Property In MFC

Microbial Fuel Cells(MFC)are devices that use bacteria attached on the electrodes as the catalysts to oxidize organic and inorganic matter and generate current.The key advantages of microbial fuel cells in comparison to conventional fuel cells are the mild operation conditions(ambient temperature,near to neutral pH)and the virtually unlimited range of potential fuels.The study of electrode materials with good conductivity and excellent biocompatibility contributes to the electron transfer,speed up the electron transport rates,adhesion of microorganisms on the surface of the electrode,leading to the increase of output potential and power in MFC.In this thesis,we focus on preparation and modification of polyaniline/chitosan grafting material,their effect as bioanode material in MFC and the enhancement of power output and energy storage.Polyaniline/chitosan grafting material were prepared via electric deposition with carbon felt as substrate.We change of chitosan’s concertration,deposition time and current density to chose the PANI/CS electrode under optimal condition.PANI/CS、PANI、CF electrode were utilized to cultivate microorganism as anode in MFC.In our study,the maxinum power output of MFC using PANI/CS electrode,PANI electrode,CF electrode as bioanode reached3026mW/m~2,2114mW/m~2,1404mW/m~2,respectively.The electric produced of each electrode were 4874C/m~2,3692C/m~2,2654C/m~2,and high current density of PANI/CS electrode were 1.173A/m~2,which is 1.24 times and 2.03 times as big as PANI electrode and CF electrode,when the cell is charged for 60 minuites and discharged for 1.5 hour.The chemical method was used to prepare PANI/CS composite,PANI and CS were connected by grafting and strong chemical bonds.PANI/CS electrode,PANI electrode and CF electrode were made via in-situ synthesis and coating.When the electrodes were prepared by in-situ syntheis,the maxnium power density of MFC using PANI/CS electrode as anode was 3553mW/m~3,which is 1.30 and 2.53 times of PANI electrode and CF electrode,respectively.While the maxnium power density of MFC using PANI/CS electrode as anode made by coating reached 4900mW/m~3,which is 1.42 times and 3.49 times of PANI electrode,CF electrode,respectively.When charging time is 60 min and discharging time is 90 min,the electric produced reached 5856C/m~2、6093C/m~2 of PANI/CS electrode made by in-situ synthesis and coating,respectively.Doped different carbon materials(carbon nanotubes、nano-carbon powder)with chitosan and prepared chitosan/carbon and PANI/CS/C composite materials.When charging time is 60min and discharging time is 90 min,the electric produced of PANI/CS/CNTs and PANI/CS/nanoC composite electrode made by in-situ synthesis reached 6756.64C/m~2、9347.91C/m~2,which is 1.15 times and 1.60 times as big as PANI/CS composite electrode made by in-situ synthesis.The maximum power density of MFC using PANI/CS/CNTs and PANI/CS/nanoC as anode that compared with CF electrode increased by 2010mW/m~3、2798mW/m~3.