Carbon nanofiber growth on graphite disks and paper for PEM fuel cells

As a clean power system, fuel cells (FCs) are known as superior electricity generators for a wide range of applications, including home appliances and cars producing water as exhaust. Carbon nano fibers (CNFs) are attractive support materials for FCs since these materials provide high electrochemically stable electrodes and effective catalyst utilization due to the high accessible surface area. The growth of CNFs was achieved on silica, alumina, carbon, and silicon in different growth conditions, such as different temperature and carbon source. Growth of CNFs on a carbon electrode has been rarely examined so far in the literature. In the present study, the growth of CNFs on two different graphite surfaces, carbon papers and graphite disks, is investigated to produce advanced electrodes for a proton exchange membrane fuel cell. On the graphite disks, the growth is rather random and mainly CNFs having diameters of 30-50 nm dominate on the surface. Nanoparticle dipping method and homogenous deposition precipitation methods are applied to investigate different deposition effects on CNF growth and morphology. One side growth of CNF on carbon paper is achieved by using a homogenous deposition precipitation of nickel with masking. The main factors that can affect the substrate selection and desired deposition method of nickel are determined as nickel loading, porosity changes of carbon paper, and the Pt loading difficulties for specific substrates.