碳纳米管预处理及CuO/CNTs燃烧催化剂的制备

Pretreatment of Carbon Nanotubes and Preparation of CuO/CNTs Combustion Catalyst

采用N-酰化法制备了氯化1-十二烷基-3-甲基咪唑鎓盐([C_(12)C_(1)Im]Cl),与十二烷基硫酸钠(SDS)和混酸(浓硫酸与浓硝酸体积比为3∶1)在碳纳米管(CNTs)预处理和纳米氧化铜(CuO)负载两方面效果进行了对比。采用ATR-FTIR研究了[C_(12)C_(1)Im]Cl的分子结构;采用SEM研究了不同预处理后的CNTs的微观形貌;采用XPS分析了CNTs负载CuO的反应机理。结果表明,成功合成了[C_(12)C_(1)Im]Cl,其分子中含有一个带正电荷的咪唑鎓亲水基团,SDS含有一个带负电荷的硫酸酯基亲水基团,可分别作为阳离子表面活性剂和阴离子表面活性剂对CNTs进行表面预处理;经[C_(12)C_(1)Im]Cl预处理后的CNTs管状清晰,管壁光滑,无团聚状态,具有优异的分散程度;CuO锚定在CNTs的缺陷位点上使得CuO稳定在CNTs表面。经[C_(12)C_(1)Im]Cl表面预处理后,可获得CuO质量分数为46.40%、分布状态均匀、高结合强度的CuO/CNTs燃烧催化剂。

The chlorinated 1-dodecyl-3-methylimidazolium chloride([C_(12)C_(1)Im]Cl)was prepared by N-acylation and compared with sodium dodecyl sulfate(SDS)and mixed acid(concentrated sulfuric acid to concentrated nitric acid in the volume ratio of 3∶1)in terms of carbon nanotubes(CNTs)pretreatment and loading effect of copper oxide(CuO)nanoparticles.The molecular structure of[C_(12)C_(1)Im]Cl was investigated by ATR-FTIR,the microscopic morphology of the CNTs after different pretreatments was carried out by SEM,and the mechanism of CuO loading on CNTs was analyzed by XPS.The results show that[C_(12)C_(1)Im]Cl is synthesized successfully,[C_(12)C_(1)Im]Cl contains a positively charged imidazolium hydrophilic group and SDS contains a negatively charged sulfate hydrophilic group,which can be used as a cationic surfactant and anionic surfactant for surface pretreatment of CNTs,respectively.The CNTs pretreated with[C_(12)C_(1)Im]Cl have a clear tubular shape,smooth walls,no agglomeration and excellent dispersion.CuO is anchored on the defective sites of the CNTs,making CuO stable on the CNTs surface.After pretreatment with[C_(12)C_(1)Im]Cl,CuO/CNTs combustion catalysts with a CuO mass fraction of 46.40%,uniform distribution state and high binding strength are obtained.