Cathode performance as a factor in electricity generation in microbial fuel cells

被引:500
作者
Oh, S
Min, B
Logan, BE [1 ]
机构
[1] Penn State Univ, Dept Civil & Environm Engn, University Pk, PA 16802 USA
[2] Penn State Univ, Penn State Hydrogen Energy Ctr, University Pk, PA 16802 USA
关键词
D O I
10.1021/es049422p
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Although microbial fuel cells (MFCs) generate much lower power densities than hydrogen fuel cells,the characteristics of the cathode can also substantially affect electricity generation. Cathodes used for MFCs are often either Pt-coated carbon electrodes immersed in water that use dissolved oxygen as the electron acceptor or they are plain carbon electrodes in a ferricyanide solution. The characteristics and performance of these two cathodes were compared using a two-chambered MFC. Power generation using the Pt-carbon cathode and dissolved oxygen (saturated) reached a maximum of 0.097 mW within 120 h after inoculation (wastewater sludge and 20 mM acetate) when the cathode was equal size to the anode (2.5 x 4.5 cm). Once stable power was generated after replacing the MFC with fresh medium (no sludge), the Coulombic efficiency ranged from 63 to 78%. Power was proportional to the dissolved oxygen concentration in a manner consistent with Monod-type kinetics, with a hall: saturation constant of K-DO = 1.74 mg of O-2/L. Power increased by 24% when the cathode surface areas were increased from 22.5 to 67.5 cm(2) and decreased by 56% when the cathode surface area was reduced to 5.8 cm(2). Power was also substantially reduced (by 78% to 0.02 mW) if Pt was not used on the cathode. By using ferricyanide instead of dissolved oxygen, the maximum power increased by 50-80% versus that obtained with dissolved oxygen. This result was primarily due to increased mass transfer efficiencies and the larger cathode potential (332 mV) of ferricyanide than that obtained with dissolved oxygen (268 mV). A cathode potential of 804 mV (NHE basis) is theoretically possible using dissolved oxygen, indicating that further improvements in cathode performance with oxygen as the electron acceptor are possible that could lead to increased power densities in this type of MFC.
引用
收藏
页码:4900 / 4904
页数:5
相关论文
共 30 条
[1]   Electrode-reducing microorganisms that harvest energy from marine sediments [J].
Bond, DR ;
Holmes, DE ;
Tender, LM ;
Lovley, DR .
SCIENCE, 2002, 295 (5554) :483-485
[2]   Electricity production by Geobacter sulfurreducens attached to electrodes [J].
Bond, DR ;
Lovley, DR .
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 2003, 69 (03) :1548-1555
[3]   Electricity generation by direct oxidation of glucose in mediatorless microbial fuel cells [J].
Chaudhuri, SK ;
Lovley, DR .
NATURE BIOTECHNOLOGY, 2003, 21 (10) :1229-1232
[4]  
DELANEY GM, 1984, J CHEM TECH BIOT B, V34, P13
[5]  
Dentel SK, 2004, P IWA C RES SLUDG SI
[6]   OXIDATION OF GLYCEROL, LACTATE, AND PROPIONATE BY PROPIONIBACTERIUM-FREUDENREICHII IN A POISED-POTENTIAL AMPEROMETRIC CULTURE SYSTEM [J].
EMDE, R ;
SCHINK, B .
ARCHIVES OF MICROBIOLOGY, 1990, 153 (05) :506-512
[7]   Operational parameters affecting the performance of a mediator-less microbial fuel cell [J].
Gil, GC ;
Chang, IS ;
Kim, BH ;
Kim, M ;
Jang, JK ;
Park, HS ;
Kim, HJ .
BIOSENSORS & BIOELECTRONICS, 2003, 18 (04) :327-334
[8]   Construction and operation of a novel mediator- and membrane-less microbial fuel cell [J].
Jang, JK ;
Pham, TH ;
Chang, IS ;
Kang, KH ;
Moon, H ;
Cho, KS ;
Kim, BH .
PROCESS BIOCHEMISTRY, 2004, 39 (08) :1007-1012
[9]   Isolation and characterization of a soluble NADPH-dependent Fe(III) reductase from Geobacter sulfurreducens [J].
Kaufmann, F ;
Lovley, DR .
JOURNAL OF BACTERIOLOGY, 2001, 183 (15) :4468-4476
[10]  
Kim HJ, 1999, J MICROBIOL BIOTECHN, V9, P365