Bacteria-loaded graphene bioanode for renewable energy generation

The high electrical conductivity and low dimensionality of graphene is essential for the development of novel lightweight bioanodes for new-generation energy technologies. However, the integration of graphene in biointerfaces presents a formidable challenge, especially because the surface energy of graphene is not compatible with living matter. Here we propose a sustainable chemical control method to reach the demanded surface hydrophilicity and conductivity of graphene nanowalls to form a lightweight, graphene-based, sponge bioanode. The few-nanometer–thick conductive graphene nanowalls create biocompatible hydrophilic microconfinements to harvest the biomass density of electrogenic Shewanella Oneidensis MR-1. The graphene-based bioanode shows a stable and rapid response with a steady-state biocurrent density of 135.35 mA m−2 realized within a few hours. Our novel and sustainable graphene-based material provides a revolutionary energy opportunity for the establishment of new energy-related graphene industries as well as facilitates many startups.