PtRu/C and PtRuBi/C electrocatalysts prepared by two different methodologies of borohydride reduction process for ethanol electro-oxidation

PtRu/C (50:50) and PtRuBi/C (50:40:10) electrocatalysts were prepared by borohydride reduction using H₂PtCl_6.6H₂O, RuCl_3.xH₂O and Bi(NO₃)_3.5H₂O as metals sources and Vulcan XC72 as support. The borohydride solution was added in two different ways: drop by drop and rapid addition of all the solution. The obtained electrocatalysts were characterized by EDX, XRD and cyclic voltammetry. The electro-oxidation of ethanol was studied by cyclic voltammetry and chronoamperometry at room temperature and on a single cell of a direct ethanol fuel cell (DEFC) at 100 deg C. PtRuBi/C electrocatalysts showed superior performance for ethanol electro-oxidation than PtRu/C electrocatalysts prepared in a similar way. However, PtRuBi/C electrocatalyst prepared by rapid addition of the borohydride solution showed superior performance for ethanol electro oxidation at room temperature, while PtRuBi/C electrocatalyst prepared by addition drop by drop of borohydride solution showed superior performance on DEFC at 100 deg C. (author)