Bifunctional cathode using a biofilm and Pt/C catalyst for simultaneous electricity generation and nitrification in microbial fuel cells

Biofouling frequently causes catalyst deterioration at the cathode of microbial fuel cells (MFCs). A biofilm-covered Pt/C cathode (BPC) was fabricated via in situ cultivation of a biofilm on a Pt/C cathode (PC) in a dual-chambered MFC, which enables effective removal of NH4(+)-N and copious generation of electricity. Experimental results show 99% NH4(+)-N removal by the nitrifying bacteria that constitute 35.7% of all microorganisms on the BPC and a maximum BPC-MFC power density of 0.97 W/m(2), which is comparable to that of PC-MFCs (0.99 W/m(2)). BPC biofilm size is restricted by the limited amount of organic material in the cathode chamber, which constrains the biomass to less than 0.3 g protein /m(2). The bifunctional-cathode equipped MFC shows great promise as an energy-saving technology for wastewater treatment in the future.