Carrier Transport Switching of Ferroelectric BTBT Derivative

Kohei Sambe; Takashi Takeda; Norihisa Hoshino; Wakana Matsuda; Kazuki Shimada; Kanae Tsujita; Shingo Maruyama; Shunsuke Yamamoto; Shu Seki; Yuji Matsumoto; Tomoyuki Akutagawa

doi:10.1021/jacs.4c00514

Carrier Transport Switching of Ferroelectric BTBT Derivative

J Am Chem Soc. 2024 Mar 27;146(12):8557-8566. doi: 10.1021/jacs.4c00514. Epub 2024 Mar 14.

Authors

Kohei Sambe¹, Takashi Takeda^{1

2

3}, Norihisa Hoshino⁴, Wakana Matsuda⁵, Kazuki Shimada¹, Kanae Tsujita¹, Shingo Maruyama¹, Shunsuke Yamamoto¹, Shu Seki⁵, Yuji Matsumoto¹, Tomoyuki Akutagawa^{1

2}

Affiliations

¹ Graduate School of Engineering, Tohoku University, 6-6-07 Aramaki Aza Aoba, Aoba-Ku, Sendai 980-8579, Japan.
² Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aoba-Ku, Sendai 980-8577, Japan.
³ Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
⁴ Department of Materials Science and Technology, Faculty of Engineering, Niigata University, 8050 Ikarashi-2, Niigata 9050-2181, Japan.
⁵ Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, Kyoto 615-8510, Japan.

PMID: 38484118
DOI: 10.1021/jacs.4c00514

Abstract

Alkylamide-substituted [1]benzothieno[3,2-b][1]benzothiophene (BTBT) derivative of BTBT-NHCOC₁₄H₂₉ (1), which has ferroelectric N-H···O= hydrogen-bonding network of alkylamide group and two-dimensional (2D) electric structure of BTBT π-cores, was prepared to design the external electric field-responsive organic semiconductors. The short-chain derivative of BTBT-NHCOC₃H₇ (1') revealed the coexistence of a 2D electronic band structure based on the herringbone BTBT arrangement and the one-dimensional (1D) hydrogen-bonding chain. 1 formed a smectic E (SmE) liquid crystal phase above 412 K and showed ferroelectric hysteresis in the electric field-polarization (P-E) curves at 403-433 K. The remanent polarization (P_r) and coercive electric field (E_c) of 1 at 408 K, 0.1 Hz were 24.0 μC cm^-2 and 5.54 V μm^-1, respectively. By thermal annealing of thin-film 1 at 443 K, the molecular assembly structure of 1 changed from a monolayer to a bilayer structure with high crystallinity, resulting in conducting layers of BTBT parallel to the substrate surface. The organic field-effect transistor (OFET) device with thermally annealed thin-film 1 showed p-type semiconducting behavior with the hole mobility of 1.0 × 10^-3 cm² V^-1 s^-1. Furthermore, device 1 showed switching behavior of semiconducting properties by electric field poling and thermal annealing cycle. The electric field response of ferroelectrics modulated the molecular orientation and conduction properties of organic semiconductors, resulting in external electric field control of carrier transport properties.