Hydrogen Fuel Cells: Replacing Oil One Step at a Time

Kenneth E.
11th Grade, Satellite High School, Satellite Beach Florida
Teacher: Joe Scott

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Abstract:One of the key factors limiting a hydrogen fuel cell from being used as a replacement for fossil fuels is the power density of a fuel cell. The power density is limited by the mass transfer resistance in the fuel cell gas diffusion layers. Many have tried replacing the gas diffusion layer with different methods but none have systematically varied porous carbons as possible potentials to minimize the mass transfer resistance.

The method used to create an array of porous carbons was to mix a carbon precursor with a highly dispersed aqueous (colloidal) suspension of silica within a ceramic boat. The mixture was then dried and cured at 100oC and 160oC for six hours in dry air, and then finally converted to a carbon/silica composite by heating at 900oC for 1 hour under a nitrogen atmosphere. The dried air and nitrogen were provided with a gas handling system which was attached to the tube allowing air and nitrogen to flow through.
The Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) showed results that carbon had formed around the silica, meaning that the silica had acted as a template as expected. The Phenol/Formaldehyde/HMS Silica derived carbon sample showed that the silica was dispersed evenly. There wasn’t a wide variation of particle size distribution within the sample. In the case of the Resorcinal/Formaldehyde/HMS Silica derived carbon the silica appears to have a larger particle size and wider particle size distribution than was expected, meaning that the silica was not dispersed properly.