Novel Crystal Engineering Strategies for High Performance Semiconducting Thienoacenes

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K14478
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Functional solid state chemistry
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: WANG CHENGYUAN 国立研究開発法人理化学研究所, 創発物性科学研究センター, 特別研究員 (20772932)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: β-Alkylthionation / Thienoacene / Crystal engineering / OFETs

Outline of Final Research Achievements

In this research project firstly efficient chemistry was established to straightforwardly introduce alkylthio groups at the β-position of various thienoacenes, through which the targeted thienoacene-based organic semiconductors were successfully developed. The packing structures of the as-synthesized materials were studied by single-crystal XRD analysis. The study revealed that by attaching certain alkylthio groups at the β-position of linear thienoacenes, the corresponding crystal structures could be generally and selectively altered into the rubrene-like packing structure, in which efficient frontier orbital overlap could be realized.
Single-crystal and thin-film OFETs were fabricated based on the as-developed materials, and some of them showed excellent performance even rivaling rubrene. The study manifested that the packing design through β-alkylthionation in thienoacenes could be a real rational material design strategy to develop high performance organic semiconductors.

Free Research Field

Chemistry

Academic Significance and Societal Importance of the Research Achievements

The research project is the first systematic study of crystal engineering of thienoacenes by alkylthionation to develop high performance organic semiconductors for OFETs, which opens a new door to rationally design materials applied in organic electronics by control of intermolcular interactions.