A novel hard-template method for fabricating tofu-gel based N self-doped porous carbon as stable and cost-efficient electrocatalyst in microbial fuel cell

A novel hard-template method to fabricate tofu-gel based N self-doped porous carbon (NC-X) as excellent oxygen reduction reaction (ORR) electrocatalyst, in which CaCO3 is in-situ formed from flocculant and then served as hard-template. The as-prepared NC-3 delivers a high specific surface area (609.10 m2 g−1), pore volume (0.68 cm3 g−1) and nitrogen content (7.20 at. %). Reasonably, NC-3 possesses more positive on-set potential (0.132 V vs. Ag/AgCl) and half-wave potential (−0.041 V vs. Ag/AgCl). Furthermore, the output voltage and maximum power density of NC-3 coated as cathode in microbial fuel cell (MFC) are enhanced to 533.65 ± 12.09 mV and 471.82 ± 15.39 mW m−2, respectively. Noted that NC-3 (2.15 × 10−3 $ g−1) also shows nice long-term stability and anti-poisoning to methanol, and is nearly 100,000 times cheaper than commercial Pt/C (20 wt %, 220.04 $ g−1). Therefore, NC-3 should be a very promising ORR catalyst in the application of MFC.