n-Doped poly(benzodifurandione) (n-PBDF) is an n-type conducting polymer with characteristics such as high electrical conductivity, solution processability, and weathering stability. Here, we systematically investigate the structure property relationship on the impact of structural modifications through aromatic substitution on the photophysical, electrical, and structural properties of n-PBDF and its oligomeric derivatives. We demonstrated that an electron donation group (methyl) raised the highest occupied molecular orbital energy level (+0.15 eV), while electron-withdrawing halogens (Br and Cl) decreased the lowest unoccupied molecular orbital energy level (−0.12 and −0.13 eV, respectively) in the polymers. Additionally, in both the undoped and doped oligomeric systems, these substitutions introduce large torsion angles (θ > 17°), causing the material to twist significantly. Moreover, the methyl-substituted polymer, n-PBDF-Me, was evaluated for its potential as a transparent organic conductor, due to its high optical transmittance (T₅₅₀ > 93%). However, n-PBDF-Me films have significantly lower conductivity than n-PBDF (0.40 vs 1330 S/cm) at similar thickness.

中文翻译：

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通过芳烃取代合成和表征 n 掺杂聚（苯并二呋喃二酮）（n-PBDF）衍生物


n 掺杂聚苯二呋喃二酮 （n-PBDF） 是一种 n 型导电聚合物，具有高导电性、溶液加工性和耐候稳定性等特性。在这里，我们系统地研究了通过芳香族取代的结构修饰对 n-PBDF 及其低聚衍生物的光物理、电学和结构性能的影响的结构性质关系。我们证明，电子供体基团 （methyl） 提高了聚合物中最高的占据分子轨道能级 （+0.15 eV），而吸电子卤素 （Br 和 Cl） 降低了聚合物中最低的未占据分子轨道能级 （分别为 -0.12 和 -0.13 eV）。此外，在未掺杂和掺杂的低聚物系统中，这些取代会引入较大的扭转角 （θ > 17°），导致材料显着扭曲。此外，甲基取代聚合物 n-PBDF-Me 由于其高透光率 （T₅₅₀ > 93%） 而被评估为作为透明有机导体的潜力。然而，在相似厚度下，n-PBDF-Me 薄膜的电导率明显低于 n-PBDF（0.40 vs 1330 S/cm）。