基于电容性阳极的微生物燃料电池串联组合及性能研究OA

[Objectives]Two distinct types of capacitive electrodes were prepared for their application in microbial fuel cell(MFC),with the primary objective of elucidating the influence of these electrodes on the electricity generation performance of individual MFC as well as series-connected MFC battery packs.A comprehensive analysis was conducted on the biomass,composition of extracellular polymeric substances(EPS),and other pertinent characteristics of the electroactive biofilm matured on the anode surface,which delved into the underlying mechanisms responsible for the observed enhancements in electricity production,operational stability,and stress resilience of MFC equipped with capacitive anodes,from a microbiological standpoint.[Methods]Manganese dioxide(MnO2)and coffee grounds-derived activated carbon(cAc)were used to modify carbon felt(CF),leading to the synthesis of MnO2@CF and MnO2/cAC@CF capacitive electrodes.Subsequently,these electrodes were employed as anodes in MFC,which were connected in series with different numbers of units to investigate the effects of capacitive anodes on the electrochemical performance of the battery packs.[Results]The implementation of capacitive anodes effectively alleviated the voltage reversal phenomena observed in series-connected MFC battery packs.Specifically,when three MFC were connected in series,the CF group exhibited a peak output voltage of 1.76 V and a maximum power density of 1 795.33 mW·m-2.In comparison,the MnO2@CF and MnO2/cAC@CF groups demonstrated elevated highest output voltages,reaching 2.01 and 2.12 V,respectively.Notably,these groups also exhibited increased maximum power densities,achieving values of 4 157.31 and 6 276.59 mW·m-2.Furthermore,the capacitive anodes facilitated the secretion of extracellular polymeric substances(EPS)by the electroactive biofilm.The protein components of these EPS enhanced the efficiency of extracellular electron transfer between the electroactive microorganisms and the electrode surface.Conversely,the polysaccharide components further augmented the environmental adaptability of the biofilm.[Conclusions]The incorporation of manganese dioxide-modified capacitive anodes not only enhanced the electricity generation performance of individual MFC but also yielded a higher output voltage,power density,and operational stability of the series-connected battery packs compared to those with CF anodes.