標題: | Influences of Conjugation Length on Organic Field-Effect Transistor Performances and Thin Film Structures of Diketopyrrolopyrrole-Oligomers |
作者: | Huang, Yi-Fan Chang, Shu-Ting Wu, Kuan-Yi Wu, San-Lien Ciou, Guan-Ting Chen, Chin-Yi Liu, Cheng-Liang Wang, Chien-Lung 應用化學系 Department of Applied Chemistry |
關鍵字: | diketopyrrolopyrrole;conjugation length;grain boundary;crystallinity;organic semiconductor |
公開日期: | 14-三月-2018 |
摘要: | Here, two diketopyrrolopyrrole (DPP)-based oligomers, DPP-4T and DPP-6T, are studied to reveal the influences of conjugation length on thin-film morphology and organic field-effect transistor (OFET) performances. PDMS-assisted crystallization in a solvent-annealing chamber is applied to prepare crystal arrays of DPP-4T and DPP-6T to optimize the quality of charge channels for OFET characterizations. To deliver insights into microstructure and morphology of thin films, a characterization procedure for determining molecular packing in thin film and crystallinity of the crystal arrays is presented via grazing incidence wide-angle X-ray scattering, electron diffraction, and lattice simulation software package (Cerius2). With the lattice parameters derived from analyses of grazing incidence wide-angle X-ray scattering (GIWAXS) and electron diffraction (ED), the lattice modeling results indicate that the inferior organic field-effect transistor (OFET) performances of DPP-6T are attributed to longer pi-stacking distance. Also, less-ordered molecular arrangement and lower continuity of crystalline domains, both of which are revealed from crystallinity results, lead to lower mobility of DPP-6T. In this case, longer conjugated backbones with more conformational degrees of freedom thus cause inherent crystal defects during the crystal growth process, despite the potential to enhance intermolecular pi-orbital overlap. Therefore, to achieve better OFET performance, suitable backbone length makes conjugated oligomers give high intermolecular pi-orbital overlap and low density of structural disorder, which are the priorities for constructing good charge channel. |
URI: | http://dx.doi.org/10.1021/acsami.7b15983 http://hdl.handle.net/11536/144706 |
ISSN: | 1944-8244 |
DOI: | 10.1021/acsami.7b15983 |
期刊: | ACS APPLIED MATERIALS & INTERFACES |
Volume: | 10 |
起始頁: | 8869 |
結束頁: | 8876 |
顯示於類別: | 期刊論文 |