这里制备了单壁和多壁碳纳米管支撑的铁-钾催化剂（定义为FeK/SWNTs和FeK/MWNTs），对其CO2加氢性质进行了评估。在CO2加氢成烯烃过程中，FeK/SWNTs（62.3％）催化剂的选择性要优于FeK/MWNTs催化剂（52.4％）。值得注意的是，对于产物为重烯烃FeK/SWNTs的选择性更高，而FeK/MWNTs对轻烯烃的选择性更高。大曲率SWNTs有更多电子富集在外表面，Hägg 碳化物丰度更高碳化物，以及与轻质烯烃更强的相互作用，可以合理化FeK/SWNTs用于CO2加氢成重烯烃的出色行为。FeK/SWNTs的催化性能在120 h稳定性测试中仅显示出轻微的变化，证明了SWNTs是一种有前景的催化剂载体，可用于从温室气体CO2中生产附加值的化学品。
 
Figure 1. (a, b) SWNTs 和 FeK/SWNTs，(c, d) MWNTs和 FeK/MWNTs催化剂的N2物理吸附等温曲线和孔径尺寸分布。                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
 
Figure 2. FeK/SWNTs和FeK/MWNTs催化剂的XRD图。
 

Figure 3. (a) FeK/SWNTs 和 (b) FeK/MWNTs 催化剂的TEM图和高斯拟合的粒径尺寸分布，图a中插图为 HRTEM 图。
 

Figure 4. （a）FeK/SWNTs 和 FeK/MWNTs催化剂的 Raman谱,
(b) 催化剂和相应支撑物的G带比较。
 

Figure 5. (a) FeK/SWNTs 和 (b) FeK/MWNTs催化剂在CO2加氢反应中的碳氢化合物产物分布。
 
     该研究工作由复旦大学Songhai Xie和Minghua Qiao课题组于2020年发表在ACS Catalysis期刊上。原文：Iron–Potassium on Single-Walled Carbon Nanotubes as Efficient Catalyst for CO2 Hydrogenation to Heavy Olefins。

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