In the present work a one dimensional steady state, mathematical model is developed to
analyse the performance of direct ethanol fuel cell (DEFC). The model considers species
mass transfer relations for flow channel, gas diffusion layer at the electrodes and multistep
bi-functional ethanol oxidation reactions at the anode catalyst layer and oxygen reduction
reaction at the cathode catalysts layer. The model takes into account diffusion and
convective effects for ethanol transport, hydraulic permeation and diffusion of gases between
the electrodes through proton exchange membrane. The model predicted well the
currentevoltage data of DEFC for different anode catalysts e.g., Pt-Re-Sn/MCN (20:5:15), Pt
eRu/MCN (20:20), Pt-Re-Sn/t-MWCNTs (20:5:15) and Pt-Re-Sn/C (20:5:15). According to the
model predictions the increase in ethanol fuel concentration equal and above 2 M leads to
higher ethanol crossover rate, parasitic current and mixed potential resulting in decrease
in current density and peak power density. However, ethanol crossover levels off or decreases
with the increase in current density within ethanol feed concentration of 1 M or
less. Thus to maximize DEFC performance or Faradaic efficiency an optimum range current
density and ethanol concentration should be used.