THE ANALYSIS OF ELECTRON TRANSFER MECHANISM WITHIN FUEL CELL SYSTEMS: ELECTROCHEMICAL AND MICROBIAL APPROACHES

Öz

Fuel cells are known as eco-friendly systems considering that only water is produced as a secondary product due to energy-producing reactions. However in order to increase the commercial usage of fuel cells, it is necessary to decrease the costs of the catalysts. In recent studies on alternative energy systems microbial fuel cell systems (MFC) with their basic structure and system allowing wastewater treatment, rise to notice. Inorganic molecules as catalysts and microorganisms instead of enzymes are used in MFCs. A majority of the catalysts are wasted in the traditional catalysts coating methods. The control of the particle size of the Pt is derived by using different powers in the coating process. The Pt-coated carbon electrodes are tested both within a Proton Exchange Membrane Fuel Cell (PEMFC) and MFC. In this study used oxidation bacteria Thiobacillus ferrooxidans on the cathode and mixed culture bacteria on the anode of MFC. As a result of using these electrodes the conductivity and ultimately the performance is increased. The performances of both fuel cell systems are investigated with electrochemical measurements. Moreover, the electron transfer mechanism at the cathode is clarified by examining the porphyrin structure of Thiobacillus ferrooxidans via quantum mechanical methods.

Anahtar Kelimeler

• microbial fuel cells
• thiobacillus ferrooxidans
• electron transfer mechanism

Kaynakça

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