Binderless carbon nanotube/carbon felt anode to improve yeast microbial fuel cell performance

Abstract

Anode is a critical component in improving the performance of microbial fuel cells (MFC). Carbon nanotubes (CNTs) anodes of varying concentrations were employed to coat carbon felt (CF) using the dyeing method without the need of any binder agent. The anode's large and conductive electrode surface area enhances the flow of electrons from the yeast to the current collector and the adhesion/growth of the biofilm. Additionally, the enhanced bioelectrochemical activity was demonstrated by complete cell electrochemical measurements on the MFC using the synthesized anode. The CF/CNT2 electrode (4% w/v of CNT) is the optimum electrode because it produces MFC comparable performance to the CF/CNT3 electrode (6% w/v of CNT). Using CF/CNT2 electrodes, yeast MFC yields voltages and Maximum Power Densities (MPDs) of 0.255 ​V and 72.46 ​mW/m2, respectively. When compared to MFCs employing CF without any modification with CNTs, these outputs were roughly 40 and 436% higher, respectively. While the glucose on the MFC substrate decreases by 95.97 ​± ​0.14%, the conductive biofilm developing on the electrode surface increases by 255 ​± ​13 ​mg, which helps to boost electron transfer fairly nicely. That seems to be, the modified CF/CNT2 anode promoted the enrichment of electro-active microorganisms.

Keywords

• Saccharomyces cerevisiae
• Binderless
• Biofilm
• Biofilm activity
• Anode structure