MFC聚苯胺碳纳米管阳极电化学法制备及其性能

Preparation and performance of graphite anode modified electrochemically by polyaniline and carbon nanotubes for MFC

引言 经济的高速可持续发展,迫切需要新能源和可再生能源的研究和开发。而微生物燃料电池（MFC）是利用电化学方法将微生物代谢能转化为电能的一种新型能源技术[1]。虽然MFC功率密度和输出电压近年来有了很大提高,但和普通氢燃料电池相比,MFC的库仑效率和输出功率都较低,

To improve power generation of microbial fuel cell,graphite anodes were modified electrochemically by polyaniline（PANI）and multi-walled carbon nanotubes（MWNTs）.Commercial MWNTs were ultrasonically treated in a mixture solution of 3∶1 concentrated sulfuric and nitric acid for 3 h.Due to production of carboxylic acid groups at defect sites of MWNTs,its solubility in HCl solution was improved.The film anodes were used in the anaerobic fluidized bed microbial fuel cell（AFBMFC）,and its performance of power production and the COD removal efficiency of wastewater were evaluated.It has been indicated that electrochemical method,including CV（cyclic voltammetry）and potentiostatic methods etc.,is of high-efficiency for preparation of electrode material,such as shorter preparation route and direct synthesis of composited film anodes as well as decrease of danger caused by use of poisonous reagents.Dopping of a small amount of MWNTs could increase significantly output electricity.Meanwhile,the optimal film anodes was prepared by potentiostatic method,containing 5%（mass） MWNT,whose maximum open-circuit voltage was 926.5 mV and power density 112.3 mW·m-2.For the optimal anodes,after running seven days,the COD removal efficiency of wastewater was 94.5%.The photos from scanning electron microscope（SEM）showed that the surface of composite film anodes was of clavate and reticular structure,in favor of adhesion of microbe and formation of biological membrane.In addition,doping MWNT can reduce the start time of MFC to about one day and improve the stability of electrodes.The maximum open-circuit voltage was 735 mV for PANI film anodes,and the performance was also better for modified anodes than for graphite rods（no modified one）.The optimal PANI film anode was prepared by cyclic voltammetry（CV）method,hydrochloric acid as proton acid and concentration 1 mol·L-1,aniline 0.1 mol·L-1,the number of polymerization cycles 24.Furthermore,the major factor influencing output voltage is matrix concentration,when it is low the output voltage is dropped quickly and stabilized in a lower value.