The Open Circuit Voltage in Biofuel Cells: Nernstian Shift in Pseudocapacitive Electrodes
Autor: | Felipe Conzuelo, Wolfgang Schuhmann, Nikola Marković, Adrian Ruff |
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Rok vydání: | 2018 |
Předmět: |
Materials science
Maximum power principle Polymers 02 engineering and technology 010402 general chemistry 01 natural sciences Catalysis Pseudocapacitance symbols.namesake Figure of merit Nernst equation Electrodes business.industry Open-circuit voltage General Chemistry 021001 nanoscience & nanotechnology 0104 chemical sciences Biofuels Electrode symbols Optoelectronics 0210 nano-technology business Oxidation-Reduction Electrode potential Voltage |
Zdroj: | Angewandte Chemie International Edition. 57:13681-13685 |
ISSN: | 1433-7851 |
Popis: | In the development of biofuel cells great effort is dedicated to achieving outstanding figures of merit, such as high stability, maximum power output, and a large open circuit voltage. Biofuel cells with immobilized redox mediators, such as redox polymers with integrated enzymes, show experimentally a substantially higher open circuit voltage than the thermodynamically expected value. Although this phenomenon is widely reported in the literature, there is no comprehensive understanding of the potential shift, the high open circuit voltages have not been discussed in detail, and hence they are only accepted as an inherent property of the investigated systems. We demonstrate that this effect is the result of a Nernstian shift of the electrode potential when catalytic conversion takes place in the absence or at very low current flow. Experimental evidence confirms that the immobilization of redox centers on the electrode surface results in the assembled biofuel cell delivering a higher power output because of charge storage upon catalytic conversion. Our findings have direct implications for the design and evaluation of (bio)fuel cells with pseudocapacitive elements. |
Databáze: | OpenAIRE |
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