Favorable Molecular Orientation Enhancement in Semiconducting Polymer Assisted by Conjugated Organic Small Molecules |
| |
Authors: | Minji Kang Jun‐Seok Yeo Won‐Tae Park Nam‐Koo Kim Dae‐Hee Lim Hansu Hwang Kang‐Jun Baeg Yong‐Young Noh Dong‐Yu Kim |
| |
Affiliation: | 1. Research Institute for Solar and Sustainable energies (RISE) Heeger Center for Advanced Materials (HCAM), School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea;2. Department of Energy and Materials Engineering, Dongguk University, Seoul, Republic of Korea;3. Department of Graphic Arts Information Engineering, Pukyong National University, Busan, Republic of Korea |
| |
Abstract: | A bimodal texturing effect of semiconducting polymers is investigated by incorporating conjugated small molecules to significantly improve the charge transport characteristics via formation of 3D transport pathways. Solution blending of the electron‐transporting polymer, poly{[N,N′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (P(NDI2OD‐T2)), with small molecular crystals of tetrathiafulvalene and tetracyanoquinodimethane is used, and the thin film microstructures are studied using a combination of atomic force microscopy, transmission electron microscopy, 2D grazing incidence X‐ray diffraction, and surface‐sensitive near‐edge X‐ray absorption fine structure. Blended thin films show edge‐on and face‐on bimodal texture with long‐range order and microstructure packing orientation preferable for electron transport through the channel in organic field‐effect transistors, which is confirmed by high electron mobility 1.91 cm2 V?1 s?1, small contact resistance, and low energetic disorder according to temperature dependence of the field‐effect mobility. Structural changes suggest a 3D network charge transport model via lamella packing and bimodal orientation of the semiconducting polymers. |
| |
Keywords: | conjugated polymers molecular orientation organic field‐effect transistors plasticizers |
|
|