铂/{还原氧化石墨烯/硅钨酸盐}_n复合物的制备及其电催化性能

利用层层自组装(LBL)结合原位光照还原法,制备了一系列{还原氧化石墨烯/多金属氧酸盐}n多层复合膜({rGO/POMs}_n),并以此作为载体,再通过恒电势法将Pt纳米粒子电沉积到复合膜载体上,得到一种P t/{rGO/SiW_(12)}_n燃料电池阳极纳米复合膜催化剂。用紫外可见分光光度计(UV-Vis)、原子力显微镜(AFM)以及扫描电子显微镜(SEM)等技术手段对载体复合多层膜的生长情况以及负载Pt纳米簇的表面形貌进行表征。结果表明,载体多层膜{rGO/SiW_(12)}_6被连续均匀地组装到了不同基底(氧化铟锡,ITO或玻碳,GC)表面且多层膜表面平整,在选定恒电势下,沉积于其表面的Pt纳米粒子具有花簇状形貌且分布均匀。比较研究了分别引入3种不同的多金属氧酸盐(硅钨酸盐SiW_(12),磷钼酸盐PMo_(12),磷钨酸盐PW_(12))制得的多层复合膜催化剂,即Pt/{rGO/SiW_(12)}_6、Pt/{rGO/PMo_(12)}_6和Pt/{rGO/PW_(12)}_6。电化学实验研究表明,在甲醇酸性溶液中,Pt/{rGO/SiW_(12)}_6复合膜相较于Pt/{rGO/PMo_(12)}_6、Pt/{rGO/PW_(12)}_6和Pt作为催化剂对甲醇氧化具有更好的电催化活性、电化学稳定性以及更优异的抗CO毒化性能,是一种颇有应用前景的燃料电池阳极催化剂。

Synthesis of Pt/{Reduced Graphene Oxide/Polyoxometalates}n Composite Films and Their Electrocatalytic Performance

A series of {Reduced graphene oxide/Polyoxometalates}_n({rGO/ POMs }_n) multilayer composite films was prepared by layer by layer assembly(LBL) combined with the light-assisted reduction in situ. The {rGO/ POMs }_n film was used as a carrier to support Pt nanoparticles electrodeposited by constant potential method to obtain a new type of fuel cell anode catalyst, namely Pt/{rGO/SiW₁₂}₆ multilayer composite film. The growth of the multilayer composite films and Pt nanoclusters' morphology were characterized by UV-visible absorption spectrum(UV-Vis), atomic force microscope(AFM) and scanning elecrton microscopy(SEM). The results indicate that the multilayer composite {rGO/ SiW₁₂}₆ is assembled on different substrate(quartz plate, indium tin oxide(ITO), and glass carbon electrode(GC)) surfaces with a continuous and uniform state, and the Pt nanoparticles on the surface exhibit a flower-like morphology. The electrochemical experiments show that Pt/{rGO/SiW₁₂}₆ catalyst exhibits better electrocatalytic activity, electrochemical stability and superior resistance to CO poisoning in the acidic methanol solution when it is compared with Pt/{rGO/PMo₁₂}₆, Pt/{rGO/PW₁₂}₆ and Pt. The Pt/{rGO/SiW₁₂}₆ multilayer composite film is expected to be the most promising methanol oxidation reaction catalyst in fuel cell anode.