One-piece adhesive-free molding polyvinylidene fluoride @Ag nanofiber membrane for efficient oxygen reduction reaction in microbial fuel cells

Abstract

The electrode and catalyst are the keys to the structure and function of the microbial fuel cell (MFC). Conventional electrodes require the use of a binder to integrate the catalytic layer of different materials with the collector layer. Here, by using a simple three-step method and polydopamine (pDA) as an anchor point, the silver is successfully anchored to polyvinylidene fluoride (PVDF) nanofibers to prepare a new PVDF@Ag nanofiber membrane (NM) electrode. This method breaks the current strategy of using carbon cloth as a carrier and coating catalyst materials on it to fabricate MFC cathodes. By using PVDF@Ag NM in MFC, the role of Ag as a catalyst can reach a power density level of 72% of commercial Pt/C (20% Pt). The chemical oxygen demand (COD) removal rate of MFC can reach 57.44% (16.76% higher than Pt/C), and the coulombic efficiency (CE) can reach 25.7%. This one-piece adhesive-free molding MFC cathode innovatively and tightly combines the current collector and the catalytic layer for the first time, providing a brand-new form of MFC cathode in the future.