Packed anode derived from cocklebur fruit for improving long-term performance of microbial fuel cells

Packed anode of microbial fuel cells (MFCs), commonly with a dense structure, suffers from the clogging, resulting in unsatisfied long-term stability of MFCs. Herein, we fabricate a biochar-based packed anode with a loose structure to enhance the long-term performance of MFCs equipped with packed anodes. The biochar, derived from cocklebur fruit, endows the packed anode with a loose structure but excellent conductivity. Once incorporated into MFCs, the biochar-based packed anode can yield comparable performance to benchmark materials. Particularly, the biochar-based MFCs present no obvious decrease of the power output during 150 days’ operation, which is attributed to the clogging-resistant effect induced by the loose structure of biochar-based anode. The cocklebur fruit-derived biochar can be a promising candidate for MFC anodes, and should facilitate both scaling-up and practical applications of MFCs.