Abstract
Microbial fuel cells (MFCs), which generate low-pollution power through feeding organic trace minerals to bacteria, are crucial for applications involving energy recovery and environmental protection. In MFCs, electrodes critically influence the electrocatalytic process. In this study, an electrical-discharge-machining (EDM)-based surface treatment method for MFC electrodes was applied to a stainless-steel mesh (SSM), which was selected as an anode substrate. The experimental results indicated that EDM surface treatment formed a recast layer on the SSM anode surface. A few defects such as cracks and notches were observed after EDM surface treatment, which increased the surface and surface roughness of the SSM anode. To verify the effectiveness of the proposed EDM treatment, an Escherichia coli (HB101)-based single-chamber MFC system was fabricated, and the electrochemical activity of the EDM-treated anode was investigated through electrochemical analysis. The maximum power density of the MFCs equipped with the untreated SSM anode and the EDM-treated SSM anode under a pulse current of 1.5 A were 101.37 and 205.94 mW m−2, respectively. Thus, EDM surface treatment increased the power generated by the MFC by a factor of approximately 2. The proposed novel EDM surface treatment, therefore, has potential for development as a standard processing procedure for metal electrode substrates.