空气稳定的氮杂蒄电子传输材料分子设计及三氮杂蒄衍生物迁移率计算
摘要
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 <italic>ortho</italic> nitrogen-substitution is the most efficient strategy stabilizing the HOMO and LUMO levels compared with the <italic>peri</italic>-and <italic>sym</italic>-substitutions. Particularly, dodecazacoronene (<bold>12ac</bold>) 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 (<bold>3b</bold>) single crystal reaches to 0.242 cm<sup>2</sup>/V s, which indicates that <bold>3b</bold> is a promising n-channel OFET material.