Optimization of a Pt-free cathode suitable for practical applications of microbial fuel cells

Microbial fuel cells (MFCs) are considered as a promising way for the direct extraction of biochemical energy from biomass into electricity. However, scaling up the process for practical applications and mainly for wastewater treatment is an issue because there is a necessity to get rid of unsustainable platinum (Pt) catalyst. In this study, we developed a low-cost cathode for a MFC making use of sputter-deposited cobalt (Co) as the catalyst and different types of cathode architecture were tested in a single-chambered air-cathode MFC. By sputtering the catalyst on the air-side of the cathode, increased contact with ambient oxygen significantly resulted in higher electricity generation. This outcome was different from previous studies using conventionally-coated Pt cathodes, which was due to the different technology used.