Effect of electrolyte pH on the rate of the anodic and cathodic reactions in an air-cathode microbial fuel cell
By He, Zhen; Huang, Yuelong; Manohar, Aswin K. & Mansfeld, Florian
Published in Bioelectrochemistry
2008
Abstract
The measurement of electricity generation from an air-cathode microbial fuel cell (MFC) with a mixed bacteria culture at different pH showed that this MFC could tolerate an initial (feed solution) pH as high as 10. The optimal initial pH was between 8 and 10 with higher current generation compared to lower or higher pH. The bacterial metabolism exhibited a buffer effect and changed the electrolyte pH. The impedance spectra of the anode and cathode of the MFC at the open-circuit potential (OCP) revealed that the anodic microbial process preferred a neutral pH and microbial activities decreased at higher or lower pH; while the cathodic reaction was improved with increasing pH.