Anderson Robin E, Barron Andrew R
Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, USA.
J Nanosci Nanotechnol. 2007 Oct;7(10):3436-40. doi: 10.1166/jnn.2007.824.
Single walled carbon nanotubes (SWNTs) may be made soluble in a range of organic solvents without sidewall functionalization via their reduction by Na/Hg amalgam in the presence of dibenzo-18-crown-6. The [Na(dibenzo-18-crown-6)]n[SWNT] complex has been characterized by UV-Visible, Raman, and AFM and is consistent with no additional sidewall functionalization as compared with raw SWNTs, while MALDI-MS shows the presence of the [Na(dibenzo-18-crown-6)]+ ion. Solubility is greatest in CH2Cl2 and DMF being comparable to surfactant dispersed SWNTs, however, measurable solubilities are also observed in hexane, toluene, and alcohols. Reaction with alkyl halides (bromohexane, 1-iodododecane) yields alkyl functionalized SWNTs (i.e., C6H11-SWNTs and C12H25-SWNTs) with an C(SWNT):alkyl ratio (ca. 40:1) significantly lower than that observed by the analogous reaction of alkyl halides with reduced SWNTs formed by the Billups method in liquid ammonia.
单壁碳纳米管（SWNTs）在二苯并-18-冠-6存在下通过钠汞齐还原，无需进行侧壁功能化即可溶于一系列有机溶剂。[Na（二苯并-18-冠-6）]n[SWNT]配合物已通过紫外可见光谱、拉曼光谱和原子力显微镜进行了表征，与未处理的单壁碳纳米管相比，没有额外的侧壁功能化，而基质辅助激光解吸电离质谱显示存在[Na（二苯并-18-冠-6）]+离子。在二氯甲烷和N，N-二甲基甲酰胺中的溶解度最大，与表面活性剂分散的单壁碳纳米管相当，不过在己烷、甲苯和醇类中也观察到了可测量的溶解度。与卤代烷（溴己烷、1-碘十二烷）反应生成烷基功能化的单壁碳纳米管（即C6H11-SWNTs和C12H25-SWNTs），其碳（单壁碳纳米管）：烷基比（约40:1）显著低于卤代烷与通过比卢普斯法在液氨中形成的还原单壁碳纳米管的类似反应所观察到的比例。
