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采用一种简单的方法合成了Pt/MnO2纳米结构催化剂.通过改变还原时间、反应温度、聚乙烯吡咯烷酮(PVP)的用量、Pt负载量等,研究了反应条件对Pt/MnO2纳米结构催化剂的Pt纳米粒子的粒径大小、粒径分布和分散性影响.并在最佳条件下合成一系列不同载体和Pt负载量的Pt/MnO2纳米结构催化剂.通过X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)等对合成的MnO2载体和Pt/MnO2催化剂进行了表征.结果表明:当还原时间为1 h、反应温度为80℃,PVP的用量为n(PVP)∶n(Pt)=20∶1时,负载的Pt纳米粒子具有较小的粒径而且能够在MnO2载体上均匀分散,Pt纳米粒子的粒径随负载量的增加先变小后增大.负载过程对载体的形貌和晶型没有显著的影响,载体不同对Pt纳米粒子的粒径没有影响,但对纳米粒子的分布密度有一定影响.
A simple method was used to synthesize Pt / MnO2 nanostructured catalysts. The effects of reaction conditions on the Pt / MnO2 nanostructured catalysts were investigated by changing the reduction time, reaction temperature, the amount of PVP and Pt loading. Size distribution and dispersion of nanoparticles, and a series of Pt / MnO2 nanostructured catalysts with different loadings and Pt loadings were synthesized under the optimal conditions. The structure of the catalysts was characterized by X-ray diffraction (XRD), scanning electron microscopy ) And transmission electron microscopy (TEM) were used to characterize the synthesized MnO2 and Pt / MnO2 catalysts. The results showed that when the reduction time was 1 h and the reaction temperature was 80 ℃, the amount of PVP was n (Pt ) = 20: 1, the loaded Pt nanoparticle has a smaller particle size and can be uniformly dispersed on the MnO2 support, the particle size of the Pt nanoparticles first decreases and then increases with the increase of the loading amount. Morphology and crystal form have no significant effect, different carrier on the Pt nanoparticles have no effect on the particle size, but the distribution of nanoparticles have a certain impact on the density.