| 초록 |
The particle size effect of a PtRu/C catalyst (E-tek) was studied by CO stripping and methanol oxidation experiments. The fresh catalyst was sintered at 300, 500, 600 and 700 oC for 3 h to increase the particle size of the fresh catalyst from 2.7 nm to 3.7, 4.7, 7.5 and 17.5 nm, respectively. From the CO oxidation, the electrochemically active surface area of the fresh catalyst decreased from 3.99 mC/cm2 to 2.32, 2.06, 1.23 and 0.48 mC/cm2 for the catalysts sintered at 300, 500, 600 and 700 oC, respectively. In the methanol oxidation, maximum activity was obtained for the catalyst sintered at 500 oC (4.7 nm). For catalysts smaller than 4.7 nm, activity decreased rapidly with decreasing particle size, while for catalysts larger than 4.7 nm, activity decreased slowly as particle size increased. |
