Although fossil fuel has contributed significantly to industrial growth globally, there is need for a more sustainable alternative energy source. This study examines the electrochemical potential of microbial fuel cell (MFC) vis-à-vis cell polarization factors. Such factors include: pH, microbial community and count, external and external environmental temperatures, and proton conductivity of ion exchange membrane. The study found that change in pH and temperature of the anolyte, and proton conductivity of the proton exchange membrane (PEM) component have direct effect on the performance of microbial fuel cell in relation to power generation and wastewater clean-up. Observed initial decrease in pH of the anolyte from 6.5 to 5.5 favoured acidophiles in the microbial community and hence increased the voltage output. However, increase in pH equally increased the voltage output more significantly up to 9.5, an indication that the consortium is predominantly alkaliphiles. Change in internal and external environmental temperature equally affected the cell operation and useful life resulting in cell polarization. However, lagging of the cell external wall with cotton wool and aluminum foil controlled the temperature and hence stabilized the output. Electrochemical impedance spectroscopy (EIS) analysis of the PEM indicates that increasing the temperature of preparation of Ekowe clay increased its proton conductivity in MFC and hence increased the cell stability and useful life. This clearly suggests that MFC power output and polarization could be kept in check by controlling critical internal and external process factors.
Obasi et al. (Fri,) studied this question.