Pd-Co/CNT复合催化剂的制备及甲醇电氧化性能

Preparation and methanol electrooxidation performance of Pd-Co/CNT composite catalysts

以Pd Cl2和Co(NO3)2为原料,采用分步乙二醇还原法制备了多壁碳纳米管负载Pd-Co复合纳米催化剂Pd-Co/CNT。利用TEM、XRD和XPS对催化剂的结构进行了表征,考察了其甲醇电氧化性能。结果显示,Co的引入使Pd催化剂的分散性得到改善,其电化学表面积可达39.7 m^(2)/g。循环伏安测试表明,当Pd∶Co物质的量比为1∶0.2时,Pd-Co/CNT的甲醇氧化峰电流密度约为Pd/CNT的2.7倍。计时电流结果表明,Co的添加使催化剂的活性衰减比例由Pd/CNT的63.8%降至54.2%,显示出较强的抗中毒能力。Pd-Co复合催化剂性能的改善归因于Pd与Co之间的协同相互作用。

Multiwalled carbon nanotube supported Pd-Co bimetallic nano-catalysts Pd-Co/CNT were prepared from PdCl2and Co(NO3)2via a step-wise ethylene glycol reduction method.The catalysts obtained were characterized by TEM,XRD and XPS,and evaluated for their methanol electrooxidation performances.The results showed that the introduction of Co improved the dispersion of Pd nanoparticles with an electrochemical surface area of 39.7 m^(2)/g.Data from the cyclic voltammetry test showed that the peak current density of the Pd-Co catalyst for methanol oxidation was about 2.7-fold that of Pd catalyst at the molar ratio of Pd to Co of 1∶0.2.The results of chronoamperometry test indicated that the addition of Co made the activity decay ratio of the catalyst decreased from 63.8%to 54.2%,showing a strong anti-poisoning ability.The improved performance of Pd-Co composite catalysts could be attributed to the synergistic interaction between Pd and Co.