透過高分子分選單壁奈米碳管是一種能夠有效獲取高純度半導體型奈米碳管的方法。而共軛高分子能夠選擇性地分選具有不同手性的半導體型奈米碳管，而共軛高分子的側鏈結構會影響這種分選能力。儘管已有大量研究通過側鏈修飾來改變共軛高分子的物理、光學和電學性質，但這些修飾對於分選半導體型奈米碳管效率的影響尚未得到充分探討。本研究探討了在萘二酰亞胺基的共軛高分子中引入各種共軛側鏈以創造雙軸延伸共軛模式的影響。具有四條辛基十二烷側鏈及苯平面分支的共軛側鏈萘二酰亞胺基共軛高分子(下以P3代稱)中，因其立體障礙(章節二)增加導致聚集能力下降，因此在甲苯溶液分散的更均勻，從而提高了包覆能力並形成更大束的高純度半導體型奈米碳管。低掠角X光繞射分析證實，共軛高分子與半導體型奈米碳管之間的相互作用是透過π–π堆疊。由P3分選出的半導體型奈米碳管所製備成的場效電晶體元件顯示出卓越的性能，其空穴遷移率相較於只有兩條辛基十二烷側鏈的萘二酰亞胺基共軛高分子(下以P1代稱)所分選出的半導體型奈米碳管製備成的元件有著顯著提高，達到4.72 cm² V⁻¹ s⁻¹，而P1只有2.21 cm² V⁻¹ s⁻¹，而前者具有較高的耐久性和偏壓穩定性。這些發現表明，雙軸延伸側鏈修飾是一種有前景的設計，可以提高使用共軛高分子對於分選半導體型奈米碳管的效率和性能。這一成就有助於開發更高效和穩定的電子器件。

Polymer-wrapped single-walled carbon nanotubes (SWNTs) are a potential method for obtaining high-purity semiconducting (sc) SWNT solutions. Conjugated polymers (CPs) can selectively sort sc-SWNTs with different chiralities, and the structure of the polymer side chains influences this sorting capability. While extensive research has been conducted on modifying the physical, optical, and electrical properties of CPs through side-chain modifications, the impact of these modifications on the sorting efficiency of sc-SWNTs remains underexplored. This study investigates the introduction of various conjugated side chains into naphthalene diimide-based CPs to create a biaxial-extended conjugation pattern. The CP with a branched conjugated side chain (P3) exhibits reduced aggregation, resulting in improved wrapping ability and the formation of larger bundles of high-purity sc-SWNTs. Grazing incidence X-ray diffraction analysis confirms that the potential interaction between sc-SWNTs and CPs occurs through π–π stacking. The field-effect transistor device fabricated with P3/sc-SWNTs demonstrates exceptional performance, with significantly enhanced hole mobility of 4.72 cm² V⁻¹ s⁻¹ and high endurance/bias stability. These findings suggest that biaxially extended side-chain modification is a promising strategy for improving the sorting efficiency and performance of sc-SWNTs using CPs. This achievement can facilitate the development of more efficient and stable electronic devices.

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