A cost-effective polyurethane based activated carbon sponge anode for high-performance microbial fuel cells

Abstract

A simple and cost-effective three-dimensional (3D) polyurethane based activated carbon sponge (ACS) MFC anode was fabricated by carbon black (CB) deposition and ammonium persulfate (APS)/H₂SO₄ oxidation. This 3D anode (denoted as APS-CB/ACS-SS) possessed remarkable ability with a maximum power density of 926 mW m⁻², which was almost 226 folds that of the untreated ACS (4.1 mW m⁻²) anode, and 2.2 folds compared with a conventional carbon cloth anode MFC (414 mW m⁻²) under the same conditions. Accordingly, the coulombic efficiency (CE) reached 13.4%, an increase of 538.1% compared with the untreated ACS anode. The results of SEM, FTIR, CV and EIS measurements demonstrated that the performance improvement was related to the changes of surface functional groups introduced by APS/H₂SO₄ oxidation, and the increase of conductivity and catalytic activity by CB coating. This study provided a new approach for cost-effective MFC anode fabrication as well as surface modification to enhance performance.