Pressurized air cathodes for enhanced stability and power generation by microbial fuel cells
KAUST Grant NumberKUS-I1-003-13
MetadataShow full item record
AbstractLarge differences between the water and air pressure in microbial fuel cells (MFCs) can deform and damage cathodes. To avoid deformation, the cathode air pressure was controlled to balance pressure differences between the air and water. Raising the air pressures from 0 to 10 kPa at a set cathode potential of −0.3 V (versus Ag/AgCl) enhanced cathode performance by 17%, but pressures ≥25 kPa decreased current and resulted in air leakage into the solution. Matching the air pressure with the water pressure avoided cathode deformation and improved performance. The maximum power density increased by 15%, from 1070 ± 20 to 1230 ± 70 mW m, with balanced air and water pressures of 10–25 kPa. Oxygen partial pressures ≥12.5 kPa in the cathode compartment maintained the oxygen reduction rate to be within 92 ± 1% of that in ambient air. The use of pressurized air flow through the cathode compartments can enable closer spacing of the cathodes compared to passive gas transfer systems, which could make the reactor design more compact. The energy cost of pressurizing the cathodes was estimated to be smaller than the increase in power that resulted from the use of pressurized cathodes.
CitationHe W, Yang W, Tian Y, Zhu X, Liu J, et al. (2016) Pressurized air cathodes for enhanced stability and power generation by microbial fuel cells. Journal of Power Sources 332: 447–453. Available: http://dx.doi.org/10.1016/j.jpowsour.2016.09.112.
SponsorsThe authors thank Dr. Xiaoyuan Zhang and David Jones for help with the manufacture of the reactor and analytical measurements. This research was supported by the Strategic Environmental Research and Development Program (SERDP), Award KUS-I1-003-13 from the King Abdullah University of Science and Technology (KAUST), the State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (Grant No. 2013DX08), the National Natural Science Fund for Distinguished Young Scholars (Grant No. 51125033), and the International Cooperating Project between China and European Union (Grant No. 2014DFE90110) and a scholarship (No. 201206120191) to W.H. from the China Scholarship Council (CSC).
JournalJournal of Power Sources