Carbonization and nitrogen plasma doping of zeolitic imidazolate framework‑8/bacterial cellulose aerogel membrane anodes for improved bioelectrocatalysis.

To address the performance bottlenecks in microbial fuel cells (MFCs), we fabricate a novel N-doped zeolitic imidazolate framework-8/bacterial cellulose aerogel membrane (N/ZIF-8/BAM), integrating two-level porous with plasma-assisted high-level nitrogen doping. Carbonized bacterial cellulose provides a three-dimensional interconnected macroporous network that facilitates Bacillus subtilis colonization and transport, while ZIF-8 derived carbon introduces nanopores to expand the electrochemical active surface area. After N2 plasma doping, N/ZIF‑8/BAM contains substantial pyrrolic N, pyridinic N, and graphitic N species. Zeta potential measurements reveal that N/ZIF‑8/BAM exhibits an overall negative surface potential (-34.6  mV), yet local positively charged N-doping sites improve bacterial adhesion at the anode interface, consistent with bacterial colonization observations. Optimized N configurations lower charge transfer resistance and promoting bio-electrocatalysis. The hierarchical porous structure enhances extracellular electron transfer between bacteria and the anode, thereby yielding a peak power density of 0.56 mW cm-2. This work offers a feasible strategy to design high-performance anodes for MFCs.