【作者】 张晋；

【导师】 韩高义； 张莹；

【作者基本信息】 山西大学 ， 无机化学， 2023， 硕士

【摘要】 高纯度半导体单壁碳纳米管（s-SWCNTs）对于下一代电子器件的构建具有至关重要的意义。然而,合成的碳纳米管通常是具有许多不同手性指数（n,m）的半导体单壁碳纳米管（s-SWCNTs）和金属单壁碳纳米管（m-SWCNTs）的混合物,其半导体纯度不能满足各种电子器件的工业要求。因此需要分离纯化后得到高纯度的s-SWCNTs,共轭聚合物包裹法因其低成本、可扩展等优势成为获得高纯度半导体单壁碳纳米管（s-SWCNTs）最有前景的方法之一。然而,纯化后的s-SWCNTs表面包裹的聚合物对电子器件有一定影响,在纯化后脱除聚合物是目前比较难解决的问题之一。本论文中,我们通过Suzuki偶联反应、aza-Wittig反应,设计合成了系列通过亚胺键连接的芴基共轭聚合物,通过超声和离心分离碳纳米管,并通过紫外-可见-近红外吸收光谱、激发-发射光谱研究了聚合物的酸刺激可裂解性和对s-SWCNTs的选择性。为不稳定性共轭聚合物的设计合成及其在碳纳米管分离方面的应用提供一定的借鉴意义。（1）通过亚胺键连接,在芴上引入噻吩、联噻吩,得到了不稳定性共轭聚合物P1和P2,实验结果表明,聚合物在非极性溶剂甲苯中对HiPco-SWCNTs（0.8-1.2 nm）和Arc-SWCNTs（1.2-1.7 nm）均表现出优异的s-SWCNTs选择性。其中（9,5）、（9,7）和（8,7）手性的s-SWCNTs含量最高。而且与传统聚合物相比,这两种聚合物在弱酸性条件下均可解聚成单体被干净地去除,从而得到无分散剂的s-SWCNTs。（2）通过醛胺自缩合反应或二醛和二胺缩合反应两种方式合成了含亚胺键共轭聚合物P3和P4,并研究了两者对s-SWCNTs的分选性质,紫外-可见-近红外光谱表明,M₁₁区峰的消失或强度降低,证明m-SWCNTs的有效消除。PLE光谱表明聚合物对（8,7）（9,4）手性的s-SWCNTs的选择性最强。此外,研究表明自缩合聚合物P3对碳纳米管分离后分散液浓度较大,而对称缩合聚合物P4对s-SWCNTs的分选纯度相对较高。两者在弱酸条件下也可以被成功解聚,得到表面无聚合物的高纯度s-SWCNTs。更多还原

【Abstract】 High-purity semiconductor single-walled carbon nanotubes（s-SWCNTs）are critical for the construction of next-generation electronic devices.However,the synthesized carbon nanotubes are usually a mixture of semiconductor single-walled carbon nanotubes（s-SWCNTs）and metal single-walled carbon nanotubes（m-SWCNTs）with many different chiral indices（n,m）,and their semiconductor purity cannot meet the industrial requirements of various electronic devices.Therefore,high purity s-SWCNTs need to be obtained after separation and purification,the conjugated polymer wrapping method has become one of the most promising methods to obtain high purity semiconductor single-walled carbon nanotubes（s-SWCNTs）due to its advantages of low cost and scalability.However,the polymer wrapped on the surface of purified s-SWCNTs has some influence on the electronic devices,and the removal of polymer after purification is one of difficulties problems at present.In this thesis,we designed and synthesized a series of fluorene-based conjugated polymers connected by imine bonds through Suzuki coupling reaction and aza-Wittig reaction,separated carbon nanotubes by ultrasonication and centrifugation,and investigated the acid-stimulated cleavability and selectivity of the polymers for s-SWCNTs through UV-Vis-NIR absorption spectroscopy and excitation-emission spectroscopy.It provides some implications for the design and synthesis of unstable conjugated polymers and their applications in carbon nanotube separation.（1）In Chapter 2,the unstable conjugated polymers P1 and P2 were obtained by introducing thiophene and dithiophene on fluorene through imine bond linkage,and the experimental results showed that the polymers haved excellent selectivity for HiPco-SWCNTs（0.8-1.2 nm）and Arc-SWCNTs（1.2-1.7 nm）in the nonpolar solvent toluene of s-SWCNTs.Among them,（9,5）,（9,7）and（8,7）had the highest content of chiral s-SWCNTs.Moreover,both polymers can be depolymerized into monomers that are cleanly removed under weakly acidic conditions compared to conventional polymers,resulting in dispersant-free s-SWCNTs.（2）In Chapter 3,the amine-containing conjugated polymers P3 and P4 were synthesized by aldehyde and amine self-condensation reactions or dialdehyde and diamine condensation reactions,and their sorting properties for s-SWCNTs were investigated.UV-Vis-NIR spectra showed the disappearance or intensity reduction of the peaks in the M₁₁region,demonstrating the effective elimination of m-SWCNTs.p LE spectra indicated that the polymers were sensitive to（8,7）（9,4）chiral s-SWCNTs with the strongest selectivity.In addition,it was shown that the self-condensed polymer P3 has a greater concentration of carbon nanotubes in the post-separation dispersion,while the symmetrically condensed polymer P4 has a relatively high sorting purity for s-SWCNTs.Both can also be successfully depolymerized under weak acid conditions,yielding high-purity s-SWCNTs without polymer on the surface.更多还原