Pt-CeO2/聚苯乙烯磺酸盐功能化碳纳米管复合物的制备及对甲醇的电催化氧化性能

Preparation and Electrocatalytic Performance for Methanol Oxidation of Pt-CeO_2/Sodium-4-styrenesulfonate Functionalized Carbon Nanotube Composites

通过阴离子聚合物聚苯乙烯磺酸钠(PSS)对碳纳米管(CNTs)进行非共价功能化修饰得到PSS功能化的碳纳米管(PSS-CNTs),利用带负电的PSS和Ce3+之间的静电作用将Ce3+组装到CNTs表面,再利用Ce3+与Pt Cl2-4之间存在的静电作用和氧化还原反应实现CeO_2和Pt纳米粒子在CNTs表面的原位沉积,得到复合催化剂Pt-CeO_2/PSS-CNTs.采用透射电子显微镜(TEM)、X射线衍射仪(XRD)、能谱仪(EDS)及拉曼光谱仪(Raman)等对催化剂进行了表征.电化学性能测试结果表明,由于PSS-CNTs表面原位沉积的Pt纳米粒子相对于在原始CNTs上沉积的Pt纳米粒子具有更小的粒径、更好的分散均匀性和稳定性,同时Pt与CeO_2之间存在良好的协同效应,Pt-CeO_2/PSS-CNTs催化剂对甲醇电催化氧化具有较好的催化活性和化学稳定性,当nPt/nCe=2/3时催化性能最优.

Carbon nanotubes（ CNTs） were noncovalently modified by anionic polymer poly（ sodium-4-styrenesulfonate）（ PSS） to obtain PSS functionalized CNTs（ PSS-CNTs）,and then Ce3＋was assembled to CNTs surface through the electrostatic interaction between electropositive Ce3＋and electronegative PSS. Through the electrostatic interaction and oxidation-reduction reaction between Ce3＋and Pt Cl2-4,CeO_2 and Pt nanoparticles were in-situ deposited on the surface of CNTs to obtain PSS-CNTs supported Pt-CeO_2 composite catalyst（ Pt-CeO_2/PSS-CNTs）. The structure, component and micromorphology of Pt-CeO_2/PSS-CNTs were characterized by transmission electron microscopy（ TEM）,X-ray diffraction（ XRD）,X ray photoelectron spectroscopy（ XPS）,energy dispersive X-ray spectroscopy（ EDS） and Raman spectroscopy,respectively. The electrochemical study shows that,due to the smaller particle size,the better dispersion uniformity and stability of Pt nanoparticles in-situ deposited on the surface of PSS-CNTs compared with those on the original CNTs,and the synergetic effect between Pt and CeO_2,Pt-CeO_2/PSS-CNTs,especially Pt-CeO_2/PSS-CNTs with nPt/nCeof 2/3,exhibits higher catalytic activity and stability for methanol electrooxidation compared with Pt-CeO_2/CNTs and PtRu/C.