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Abstract
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Fuel cells can work with every fuel source to generate high-efficiency power with low emissions.
Enzymatic glucose fuel cell is one of the promising low-power portable devices which can be
used for medicinal implants. One of their challenges is their extremely low power and short
durability. In this study, a Direct Glucose Fuel Cell (DGFC) was modeled by computational fluid
dynamics using COMSOL Multiphysics® software. The performance of the fuel cell was
evaluated by modeling of mass transport of reactants, products, and intermediate species, together
with reaction kinetics and ohmic resistance effects. Also, concentration profiles of chemical
components and the temperature distributions in each layer of DGFC have been predicted.
Validation of the model was well confirmed with experimental data. The effect of anodic
overpotential was significant relative to that of cathodic and ohmic overpotentials because of the
complexity of the glucose electro-oxidation. The enhancement of reactants concentration,
temperature, and cathode side pressure caused to improvement in the DGFC performance while
the increase in membrane thickness has an adverse effect on the cell voltage.
A DGFC can oxidizes glucose at anode and reduces oxygen at cathode to give electric energy
through electrocatalysis (Fig. 1A). To enhance the performance, it is necessary to reduce
overpotentials and increase the turnover to. Generally, glucose would be oxidized using two
electron/two proton and generate gluconolactone whereas oxygen is reduced via a four
proton/four electron process to produce water. Because of continuous consumption of glucose
and oxygen in physiological fluids by the metabolism, this procedure is able to support sufficient
energy over the patient lifetime without any need of power supply facility.
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