Noncovalent Se center dot center dot center dot O Conformational Locks for Constructing High-Performing Optoelectronic Conjugated Polymers

摘要

Noncovalent conformational locks are broadly employed to construct highly planar -conjugated semiconductors exhibiting substantial charge transport characteristics. However, current chalcogen-based conformational lock strategies for organic semiconductors are limited to SX (X = O, N, halide) weak interactions. An easily accessible (minimal synthetic steps) and structurally planar selenophene-based building block, 1,2-diethoxy-1,2-bisselenylvinylene (DESVS), with novel SeO noncovalent conformational locks is designed and synthesized. DESVS unique properties are supported by density functional theory computed electronic structures, single crystal structures, and experimental lattice cohesion metrics. Based on this building block, a new class of stable, structurally planar, and solution-processable conjugated polymers are synthesized and implemented in organic thin-film transistors (TFT) and organic photovoltaic (OPV) cells. DESVS-based polymers exhibit carrier mobilities in air as high as 1.49 cm(2) V-1 s(-1) (p-type) and 0.65 cm(2) V-1 s(-1) (n-type) in TFTs, and power conversion efficiency >5% in OPV cells.