Abstract:

It was found that when the Pd/C catalyst as the anodic catalyst in the direct formic acid fuel cell (DFAFC) is prepared with the improved liquid phase reduction method the Pd/C catalyst with small average size and relative crystalinity of the Pd particles can be prepared if the suitable amount of NaOH is added before the addition of NaBH4. The average size and relative crystalinity of the Pd particles in the Pd/C catalyst prepared are related to the concentration ratio of NaOH and PdCl2. The average size and relative crystalinity of the Pd particles in the Pd/C catalyst prepared without addition of NaOH are 20.2 nm and 6.29, respectively. When the concentration ratio of NaOH and PdCl2 is 10 The average size and relative crystalinity of the Pd particles in the Pd/C catalyst prepared are as small as 6.7 nm and 3.45, respectively. Thus, this Pd/C catalyst showed the excellent electrocatalytic activity and stability for the oxidation of formic acid. Because the improved liquid phase reduction method is simple, it may obtain the practical application.

Key words: formic acid, direct formic acid fuel cell, carbon supported Pd catalys, sodium hydroxide, liquid phase reduction method