Development of Chitosan Membranes as a Potential PEMFC Electrolyte

Abstract

Commercial chitosan and chitosan extracted from shrimp shells are being used to design membranes to be tested as low cost electrolyte in PEM fuel cells. This study investigated the influence of the deacetylation degree (DD) and molar mass (M V ) of the chitosans used in the composition of membranes on its performance regarding to proton conductivity and other properties. Preliminary results indicate that the chitosan extracted from shrimp shells generated membranes with promising properties such as proton conductivity, which demonstrated to be even a 100 times higher than those shown by commercial chitosan membranes. The significant increase in proton conductivity can be associated with the higher number and availability of amino groups (–NH2) in the chitosan produced in the laboratory, which presents higher DD and lower M V . It is believed that the properties of chitosan can be manipulated in such a way that it would be possible to obtain proton conductivity values closer to that presented by Nafion®.