聚乙酰苯胺修饰碳纳米管载铂催化剂对甲醇电催化氧化

Electrocatalytic Oxidation of Methanol with Poly(N-acetylaniline) Functionalized Multiwalled Carbon Nanotubes Supported Pt Catalysts

以原位化学聚合的聚乙酰苯胺/多壁碳纳米管(PAANI-MWCNTs)复合纳米材料作为载体,采用硼氢化钠还原法将Pt纳米粒子担载到PAANI-MWCNTs复合纳米材料表面,制备了Pt/PAANI-MWCNTs复合纳米催化剂.样品的结构和形貌用紫外-可见(UV-Vis)光谱、拉曼光谱、扫描电镜(SEM)、透射电镜(TEM)和X射线衍射(XRD)进行了表征.结果表明,聚乙酰苯胺与碳纳米管之间存在较强的π-π相互作用,使其能牢固地吸附于多壁碳纳米管表面,对碳纳米管的结构完整性和导电性有一定的改善作用.同时,金属Pt纳米颗粒较为均匀地分散在PAANI-MWCNTs表面,粒径分布范围较窄.采用循环伏安法和计时电流法在酸性溶液中研究了Pt/PAANI-MWCNTs催化剂对甲醇的电催化氧化活性,结果表明Pt/PAANI-MWCNTs复合纳米催化剂比用混酸处理的碳纳米管载铂催化剂对甲醇呈现出更高的电催化氧化活性和更好的抗中毒能力及稳定性.

A novel process to prepare well-dispersed Pt nanoparticles on poly（N-acetylaniline） functionalized multiwalled carbon nanotubes （Pt/PAANI-MWCNTs） using chemical in situ polymerization and reduction is reported. Scanning electron microscopy （SEM）, transmission electron microscope （TEM）, X-ray diffraction （XRD）, UV-Vis absorption spectroscopy as well as Raman spectroscopy were used to characterize the catalyst. We found that PAANI can easily immobilize onto the MWCNTs because of a strong interaction with the basal plane of graphite via π-stacking. The Pt particles supported on the PAANI-MWCNTs are uniformly dispersed with a narrow particle size distribution. The electrocatalytic activity of the Pt/PAANI-MWCNTs towards the oxidation of methanol was investigated using cyclic voltammetry and chronoamperometry. The results indicate that the Pt/PAANI-MWCNTs catalysts exhibit higher electrocatalytic activity, better anti-poisoning ability, and good stability during methanol oxidation in comparison to the Pt/MWCNTs for acid oxidation （Pt/AO-MWCNTs）.