Electrochemical Characterization of Glassy Carbon/CNT/Chit Scaffold-Attached Biofilms Under Linear Flow Conditions

Improvements on carbon-base anode modified with carbon nanotubes (CNT’s) and chitosan polymer (Chit) have been accomplished for the bacteria attachment and better electron transfer in microbial fuel cells by coupling Chit to CNT’s. Arrangements of this nature can be structured into 3D macroporous scaffolds possessing large pore sizes that support bacterial colonization. This work describes the electrochemical and high surface resolution characterization of the growth of thin (<20 µm) biofilms on glassy carbon electrodes modified with Chit dispersed into multiwalled carbon nanotubes (MWCNT). Cyclic Voltamperometry (CV) and Electrochemical Impedance Spectroscopy (EIS) are applied to characterize and assess the interfacial response in anaerobic conditions under laminar flow conditions. In vivo analysis of electron transfer between bacterial cells and electrodes provides insight into the main redox-active species participating in electron transfer to electrodes. CV and EIS also reveal features that are consistent with detections of multiple redox-active species appearing at the outer surfaces of this biofilm with electron transfers. The results are fitted to equivalent analogs. These techniques illustrates specifics quantifiable parameters and defined electron transfer processes as a function of potential, electrode material, growth phase, and culture conditions.