空气稳定的氮杂蔻电子传输材料分子设计及三氮杂蔻衍生物迁移率计算

采用密度泛函理论研究氮功能化对蒄类化合物几何构型、电子结构及载流子传输性质的影响. 结果表明, 引入杂N原子可以线性降低前线轨道能级, 增强电子注入能力与空气稳定性, 且邻位掺杂较迫位和均匀掺杂调节效果更为显著. 其中, 十二氮杂蒄（12ac）具有新颖的“碗状”构型和高的电子亲和势（3.45 eV）, 是潜在的空气稳定电子传输材料构筑单元. 理论预测室温下2,6,10-三对甲氧基苯基-3,4,7,8,11,12-六甲氧基三氮杂蒄（3b）晶体的电子迁移率为0.242 cm2/V s, 预计是良好的电子传输材料, 值得进一步器件化研究.

Molecular design toward air-stable electron transport materials based on N-heterocoronenes and charge mobility prediction for the 1,5,9-triazacoronene derivative

The successive replacement of CH moieties by nitrogen atoms in coronene was studied computationally using the density functional theory （DFT）. And the effects of different N-substituted patterns on geometries, electronic properties, and charge transport parameters were discussed in detail. The results show that the frontier molecular orbital energies decrease linearly with the increase of the number of nitrogen atoms, which is not only ideal for electron injection but also contribute to improved air stability of these semiconductors. Relatively, the ortho nitrogen-substitution is the most efficient strategy stabilizing the HOMO and LUMO levels compared with the peri-and sym-substitutions. Particularly, dodecazacoronene （12ac） with a unique ＂bowl-shape＂ structure may be a potential building block as air-stable n-channel materials due to its large electron affinity （3.45 eV）. In addition, the predicted room-temperature electron mobility for 2,6,10-tri（4-methoxyphenyl）-3,4,7,8,11,12-hexamethoxy-1,5,9-triazacoronene （3b） single crystal reaches to 0.242 cm2/V s, which indicates that 3b is a promising n-channel OFET material.