摘要: | 本論文為有機薄膜電晶體的材料開發,成功以吡咯併吡咯二酮單元為核心,並外接 3-(二氰基亞甲基)茚-1-酮 (IN) 與 5,6-(二氯)-3-(二氰基亞甲基)茚-1-酮 (INCl),合成出四個 n 型有機薄膜電晶體材料 DIN-DPP-b20 (1)、DINCl-DPP-b20 (2)、DIN-DPP-b16 (3)、DINCl-DPP-b16 (4)。 Diketopyrrolopyrrole (DPP) 單元具有高的平面性及其有缺電子的性質和形成氫鍵的能力,導致其有很強的 π-π-stacking 作用及分子內電荷轉移作用,為一良好之OTFT的核心。利用 Uv-vis 探討此系列分子之吸收度差異,接上含氯之拉電子基團 INCl 之化合物(2)和(4),相較化合物(1)和(3)有明顯的紅位移,再利用 DPV 探討所開發分子之 HOMO 與 LUMO 能階之差異。化合物(2)與(4)具 INCl 之 HOMO 與 LUMO 能階相較於化合物(1)與(3)都有明顯的下降。因其核心及外掛基團均具有良好平面性,期望提高薄膜的結晶性及元件的電性效能。 延續實驗室之前開發具硫醚鏈噻吩的研究,開發出四個以具硫醚鏈聯噻吩 SBT 為核心的化合物,並外接 3-(二氰基亞甲基)茚-1-酮 (IN) 與 5,6-(二氯)-3-(二氰基亞甲基)茚-1-酮 (INCl),合成出四個 n 型有機薄膜電晶體材料 DIN-SBT-14 (5)、DINCl-SBT-14 (6)、DIN-SBT-b16 (7)、DINCl-SBT-b16 (8)。利用 Uv-vis 探討此系列分子之吸收度差異,接上含氯之拉電子基團 INCl 之化合物(6)和(8),相較化合物(5)和(7) 有明顯的紅位移,再利用 DPV 探討所開發分子之 HOMO 與 LUMO 能階之差異。化合物(6)與(8)具 INCl 之 HOMO 與 LUMO 能階相較於化合物(5)和(7)都有明顯的下降。藉聯噻吩上 ii 的 S 原子和硫醚鏈上 S 原子之間的分子內作用力,使得核心結構有更好的平面性,有利於電子的傳遞。;A series of diketopyrrolopyrrole (DPP)-based and thioalkylated bithiophene (SBT) small molecules were developed for organic thin film transistors (OTFTs). For the first series, the DPP cores with different alkyl chains were end-capped with electron withdrawing groups, such as dicyanomethylene indanone (IN) and dichlorodicyanomethylene indanone (INCl), to give four new small molecules, DIN-DPP-b20 (1), DINCl-DPP-b20 (2), DIN-DPP-b16 (3), and DINCl-DPP-b16 (4). The four DPP molecules have almost identical HOMOs. As expected, the LUMOs of the two chlorinated DPPs (DINCl-DPP-b20 (2) and DINCl-DPP-b16 (4)) were lower than those of DIN-DPP-b20 (1) and DIN-DPP-b16 (3), resulting a larger energy gap of the latter. This can be attributed to the electron withdrawing characteristic of the chlorine atoms. For the second series, the SBT cores with different alkyl chains were end-capped with electron withdrawing groups, IN and INCl, to give four new small molecules: DIN-SBT-14 (5), DINCl-SBT-14 (6), DIN-SBT-b16 (7), and DINCl-SBT-b16 (8). Similar to the DPP series, the four SBT molecules have almost identical HOMOs and the LUMOs of the two chlorinated SBTs (6 and 8) were lower than those of 5 and 7. Therefore, these two chlorinated SBTs exhibit smaller energy gap in the UV-Vis absorption in comparison to those non-chlorinated analogs. |