1. Abstract Pt-Ru/C catalyst has been applied extensively in direct methanol fuel cells for methanol electrochemical oxidation. In this study, a model for electrochemical kinetics of methanol has been developed for electrocatalyst Pt-Ru/C. The single cell performance of DMFC and AC impedance analysis were measured. The methanol crossover problem still remains a challenge for the applications of...

To suppress methanol crossover in direct methanol fuel cells DMFCs , a Nafion-Bi2V0.75Sb0.25O5.4 composite membrane was prepared by recast method. Oxygen-ion conductive Bi2V0.75Sb0.25O5.4 powders were highly dispersed in a Nafion 117 membrane to physically block methanol crossover and/or chemically oxidize the methanol, which was confirmed by the difference in the methanol diffusion coefficient...

Two modifications to a reference direct methanol fuel-cell (DMFC) system are considered to improve methanol fuel utilisation. Fuel utilisation can be optimised by minimising the parasitic methanol crossover by manipulating methanol concentration in the fuel cells. Simulations of the two systems indicate that there is considerable potential to increase fuel utilisation for dynamic concentration ...

It is important to have accurate, reliable, and convenient techniques for determining the methanol crossover rate through the polymer electrolyte membranes of fuel cells. In this work, various electrochemical techniques, namely; cyclic voltammetry, chronoamperometry and potentiometry, have been used to measure the methanol crossover rates using Nafion 117 membrane. The purpose of using differen...

Passive direct methanol fuel cells (DMFCs) are promising energy sources for portable electronic devices. Different from DMFCs with active fuel feeding systems, passive DMFCs with nearly stagnant fuel and air tend to bear comparatively less power densities. A steady state, one-dimensional, multi-component and thermal model is described and applied to simulate the operation of a passive direct me...

Proton exchange membranes (PEM) for a direct methanol fuel cell (DMFC) have main drawbacks which are methanol permeability, reduced proton conductivity and the cost of the membrane. This paper reviews different polymeric materials such as fluorinated, non-fluorinated, acid-base complex, and composite membranes for DMFC. Currently, nonfluorinated membranes gain a lot of atte...