Molecular engineering of buckybowl trichalcogenasumanene toward centimeter-sized organic single-crystal arrays and devices
Organic semiconductor single-crystal (OSSC) arrays are pivotal for high-performance integrated electronics, yet the fundamental principles governing molecular design for one-dimensional (1D) crystalline nanostructures and the role of intermolecular interactions in solution self-assembly remain unresolved. This study introduces a molecular engineering strategy employing hetero-buckybowl trichalcogenasumanenes to direct the self-assembly of OSSC arrays. The distinctive concave-convex architecture promotes 1D crystal formation via directional π-π interactions while suppressing intercolumnar coupling, thereby enhancing structural anisotropy and charge transport. Centimeter-sized OSSC arrays were fabricated on various substrates through solution self-assembly. Organic field-effect transistors (OFETs) based on these arrays exhibited hole mobility up to 0.89 cm² V⁻¹ s⁻¹ (average 0.65 cm² V⁻¹ s⁻¹), with minimal device-to-device variation, surpassing previous buckybowl-based devices. The six butoxy groups in molecule 4 improve solubility and stabilize molecular morphology against strain, yielding flexible OFETs with outstanding bendable durability. This strategy significantly enhances crystallinity and uniformity, offering a pathway for high-performance, large-area organic electronics.