用改进液相还原法制备炭载Pd催化剂

Pd/C catalysts Prepared with Improved Liquid Phase Reduction Method

研究了用改进液相还原法制备用作直接甲酸燃料电池(DFAFC)的炭载Pd(Pd/C)阳极催化剂制备方法,研究发现在滴加还原剂NaBH4之前,在PdCl2溶液中滴加NaOH溶液后,制得的Pd/C催化剂中Pd粒子的平均粒径和相对结晶度均比不加NaOH的小。而且Pd粒子的平均粒径和相对结晶度与加入的NaOH溶液和PdCl2溶液的浓度比有关。在未加NaOH时制得的Pd/C催化剂中Pd粒子的平均粒径和相对结晶度分别为20.2 nm和6.29,当加入的NaOH溶液和PdCl2溶液的浓度比为10时得到的Pd粒子的平均粒径和相对结晶度适中,分别为6.7 nm和3.45,因此,制得的Pd/C催化剂对甲酸氧化的电催化活性和稳定性均要比其它NaOH溶液和PdCl2溶液的浓度比时制得的Pd/C催化剂要好。且该制备方法简单,具有潜在的应用前景。

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,where Pd/C catalyst with small average size and relative crystalinity of the Pd particles can be prepared if suitable amounts of NaOH are added before the addition of NaBH4.The average size and relative crystalinity of 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 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 Pd particles in the Pd/C catalyst are 6.7 nm and 3.45,respectively,which exhibits an excellent electrocatalytic activity and stability for the oxidation of formic acid.Because the improved liquid phase reduction method is simple,it may have the potential for practical applications.