π-Extended Zigzag-Shaped Diphenanthrene-Based p-Type Semiconductors Exhibiting Small Effective Masses

Abstract

Molecular design strategy of the π-electron core is of importance to enhance the organic semiconducting performance. In this study, diphenanthro[1,2-b:2′,1′-d]thiophene (DPT) as a new zigzag-shaped sulfur-bridged π-electron core and its phenyl-substituted derivative (Ph–DPT) exhibiting unique orbital configurations are reported. The DPT derivatives are readily synthesized through a versatile synthetic scheme in five steps from the commercially available dibenzothiophene. Their single-crystal structural analyses and band calculations revealed that both DPTs form typical herringbone packing structures, which are favorable for 2D charge carrier transport, along with small effective masses. Single-crystal-based field-effect transistors (FETs) of both DPT and Ph–DPT exhibit p-type behaviors and charge-carrier mobility up to 5.5 cm² V^–1 s^–1. These results provide information that can broaden the molecular design approaches toward high-performance organic semiconductors.