Development of the direct borohydride fuel cell catalysts

With the increasing world population, energy consumption is increasing day by day. The damage caused by the use of fossil fuels to the environment is seen as a major problem. Many of these problems can be alleviated by using clean and renewable energy sources. As a clean energy source, hydrogen is one of the most suitable alternative energy sources. Hydrogen fuel cells are successful in producing efficient energy. Fuel cells using borohydride as fuel are preferred because of their high potential and power density In this master thesis, carbon nanotube (CNT) supported Pt-based bimetallic and monometallic catalysts were synthesized by NaBH4 reduction method to be used directly in sodium borohydride fuel cells. The activities of bimetallic PtAu (50:50)/CNT, PtAu (70:30)/CNT, PtAu (90:10)/CNT and PtCu (70:30)/CNT, PtIr (70:30)/CNT, Au/CNT, Cu/CNT, Pt/CNT, Ir/CNT catalysts synthesized in different mole ratios for the borohydride (BH4-) electrooxidation reaction were investigated by voltammetry, chronoamperometry and electrochemical impedance spectroscopy methods. PtCu (70:30)/CNT bimetallic catalyst showed higher activity for borohydride oxidation reaction. Keywords: Bimetallic catalysts, borohydride electrooxidation, carbon nanotubes, platinum, sodium borohydride