Green composite papers via use of natural binders and graphene for PEM fuel cell electrodes

Official URL: http://dx.doi.org/10.1021/acssuschemeng.7b02207

Herein a new fabrication method was suggested via paper molding process for preparation of gra-phene/cellulose/carbon fiber composite paper to be used as the flexible electrode layers mainly for PEM fuel cell. As a green and eco-friendly process, composite papers were prepared at ease with no pollutant by product formation by using ionic liquids (IL). At first carbon fibers bound via cellulose fiber to form cellulose/carbon fiber composite paper by wet-laying. Then, electrical conductivity as well as hydrophobicity of the composite papers were improved by extraction of cellulose via ionic liquid-assisted phase inversion method and then gra-phene inserted to the structure of ionic liquid treated composite paper by spray coating. Moreover, by spray coating of 0.5 mg cm-2 platinum (Pt) catalyst to the mentioned composite papers, significant improvement in their fuel cell performances were achieved at low relative humidity (RH) fuel cell operation conditions (RH <50%) what increases the overall system efficiency. The highest power density was recorded at 50% RH as 911 mW cm-2 which was over 20% higher than the 100% RH operating conditions.