Material specific enrichment of electroactive microbes on polyaniline-supported anodes in a single chamber multi-anode assembly microbial fuel cell

Abstract

In the present study different polyaniline (PANI) supported nanocomposites electrodes have been prepared for the material-specific enrichment of electrogens on the surface of multi-anode assembly based microbial fuel cell (MFC). In this regard, eight different polyaniline (PANI)-based nanocomposite anode materials have been successfully fabricated to develop different electroactive microbial biofilms inside the MFC with a shared air-cathode. Significant development of microbial community on all anodes was confirmed by SEM analysis. The developed anodes utilized inside the MFC produced the maximum power densities viz. PANI-CNT/MOF/G (204.42 mW/m2), PANI-CNT/G (200.73 mW/m2), PANI-CNT/MOF (322 mW/m2), PANI-CNT (222.31 mW/m2), PANI (130.81 mW/m2), PANI-G (156 mW/m2), PANI-MOF (159 mW/m2) and PANI-CNT/G/TiO2 (181.89 mW/m2). Among all anodes, higher exoelectrogenic activity was observed on PANI-CNT/G/TiO2 nanocomposite. Likewise, eleven culturable microbial species (Achromobacter denitrificans, Achromobacter xylosoxidans, Burkholderia cepacia, Burkholderia cenocepacia, Burkholderia fungorum, Candida tropicalis, Enterobacter cloacae, Enterobacter kobei, Escherichia coli, Pseudomonas aeruginosa and Pseudomonas citronellolis) in bacterial biofilms have been subsequently identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). Based on the growth of distinguished biofilms (which were both exoelectrogenic as well as electrotrophic) on different developed nanocomposite based anodes present in the same MFC setup. The nanocomposites based multi-anode assembly MFC having shared air cathode can have applications in treating complex wastewaters.