A novel and utilized electrode with boosted biofilm formation and current generation in microbial fuel cells based on chitosan/carbon composite

Abstract

The successful application of bioelectrochemical systems in the future depends on the improving of electrode performance while decreasing material costs. This study explores the use of chitosan supported on different kinds of carbon materials to modify graphite electrode for the electricity generation performance of Geobacter sulfurreducens. The novel hierarchically carbon composites modified electrodes were obtained by a simple and environment-friendly method. Among the proposed composites, the optimal composite CS/CB (5 h) possessed a better performance for the promotion of electrochemically active biofilm (EAB) growth and enhancing current generation compared with other composites. Based on morphological, chemical, and electrochemical evidences, we conclude that the CB was coated on the surface of CS to form the CS/CB decorated graphite electrode, and CS/CB (5 h) electrode exhibited significant load-bearing capacity for bacteria colonization and enhanced the contact between bacteria and electrode, which improved the direct electron transfer process. The microbial three-electrode system equipped CS/CB (5 h) device delivered a high current density of 1457±69 μA/cm2. The current density was increased to 3 times higher than that of the unmodified electrode. The use of this CS/CB (5 h) composite can substantially improves EAB growth and enhance power production of bioelectrochemical systems.