Preparation of carbon composite from coconut fiber for gas diffusion layer

A natural carbon from coconut fiber is used as a main composite material of gas diffusion layer (GDL) for fuel cell electrode. The composite comprise of polymer (ethylene vinyl acetate and poly ethylene glycol) and carbon in various compositions. The materials are mixed in xylene and printed using casting method. The composite is coated with polytetrafluoro ethylene (PTFE) to achieve hydrophobic requirement as GDL. The electrical properties of composite were measured by using LCR-meter, the porosity was obtained by immersion method, and the hydrophobic properties were observed by measuring its contact angle. The results show the electrical conductivity of GDL prepared corresponds to its carbon content. The electrical conductivity of GDLs is 22.17, 26.89, 35, 43, and 52 S/m for the carbon composition of 65, 70, 75, 80, and 85 %, respectively. The composite of 80 % carbon content and coated with PTFE contains 74 % porosity and has desired hydrophobic properties revealed from its high contact angle, i.e., 120°.