Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 2, 2015
Previous Article Next Article

Use of low cost and easily regenerated Prussian Blue cathodes for efficient electrical energy recovery in a microbial battery

Author affiliations

Abstract

Microbial fuel cells can directly convert chemical energy into electrical energy, but significant energy losses result from the use of O2 as the cathode. Microbial batteries (MBs) replace conventional O2 cathodes with solid-state cathodes that can be re-oxidized under favorable conditions, enabling more efficient energy recovery. Previously, we demonstrated proof-of-concept for MBs with a silver oxide cathode. The high cost of silver and energy required for re-oxidation make this material impractical. In this work, we evaluate Prussian Blue (PB), a hexacyano-Fe complex material, as a low-cost solid-state cathode in a single-chamber, membrane-free MB. Microbial oxidation of organic matter at the anode drives the reduction of PB. Reduced PB is re-oxidized by exposure to air. MBs equipped with a PB electrode efficiently transfer charge to PB (85% charge transfer), achieving net energy recovery efficiencies of 18–33%, with no loss of capacity over 20 cycles of operation. The operating potential for the PB electrode creates a trade-off: increasing the PB electrode potential improves the efficiency of energy recovery, but more material is required to maintain power output and ensure efficient oxidation of organic matter. Operation is otherwise straightforward: energy is only required to move reduced PB into the air then back to the MB. We conclude that PB is a promising cathode material for single-chamber, membrane-free MBs.

Graphical abstract: Use of low cost and easily regenerated Prussian Blue cathodes for efficient electrical energy recovery in a microbial battery

Back to tab navigation

Supplementary files

Article information


Submitted
15 Oct 2014
Accepted
18 Dec 2014
First published
18 Dec 2014

Energy Environ. Sci., 2015,8, 546-551
Article type
Communication
Author version available

Use of low cost and easily regenerated Prussian Blue cathodes for efficient electrical energy recovery in a microbial battery

X. Xie, M. Ye, C. Liu, P. Hsu, C. S. Criddle and Y. Cui, Energy Environ. Sci., 2015, 8, 546
DOI: 10.1039/C4EE03268C

Social activity

Search articles by author

Spotlight

Advertisements