Study On The Performance Of The Cathode Of Phosphide Pentoxide/biomass Carbon Microbial Fuel Cell

Microbial fuel cells?MFCs?as a sustainable bioelectricity-generated technology,which can generate electricity while treating wastewater,has received increasing attention all over the world.Study of MFCs not only leads a new way for developing renewable energy sources,but also helps solving environmental problems.At present,an important factor that limits the the extensive application of MFCs is the low efficiency of oxygen reduction reaction?ORR?.To improve the ORR efficienty in MFCs cathodes and boost the power generation of MFCs,novel catalysts of cathode with low-cost have been developed.In this study,the prepared catalysts are characterized by XRD,BET,XPS,SEM,TEM and other measurements to evaluate the structure characters of materials.CV,LSV and RDE are also measrured to test the electrochemical properties of the composites.The nitrogen-doped cobalt/cobalt phosphide/carbon?Co/Co₂P/NC?catalysts is prepared via an in situ simultaneous synthesis method by using cornstalks as carbon source,which not only meets the recycle of wastes,but also lowers the cost of the materials.During the study,the impact of carbonization temperature towards the structural characteristics and the electrocatalytic activity are analyzed.MFCs with Co/Co₂P/NC-850 cathodes obtain the maximum power density of 972 mW m^-2 and the lowest charge transfer resistance of 0.93?.The good durability of Co/Co₂P/NC-850catalysts during the operation of MFCs is the guarantee of the stable power output.To further optimize the performance of MFCs,Co/?FeCo?/Co₂P/NC composites are synthesized by introducing the FeCl₃ into Co/Co₂P/NC during the preparation process.Effects of carbonization temperature on the prepated materials are still discussed.Compared with other catalysts,Co/FeCo/Co₂P/NC-950 shows the highest electrocatalytic activity.ORR catalyzed by Co/FeCo/Co₂P/NC-950 is mainly via 4e^-reaction pathway.During the operation of the MFCs,MFCs with Co/FeCo/Co₂P/NC-950 cathodes obtain the maximum power density of 997.7 mW m^-2and the highest voltage output of 0.557 V.Despite of the enhancement of electrocatalytic activity of catalysts,the durability of MFCs with Co/FeCo/Co2P/NC is also improved,which can be attributed to the introduction of Fe species.Herein,the prepared N-doped non-noble transition metals phosphides decorated carbon-based materials with the advantages of low-cost,environmental-friendly and high efficiency may provid new references for developing efficient and stable ORR catalysts.