High Thermally Stable n-Type Semiconductor up to 850 K Based on Dianionic Naphthalenediimide Derivative

Abstract

Electrostatic cation–anion interaction is effective to form a tightly bounded π-molecular assembly, which enhances the thermal stability and carrier transport property. Dianionic bis(benzenesulfonate)–naphthalenediimide (BSNDI2–) formed simple 2:1 cation–anion pairs of (Na+)2(BSNDI2–) (1), (K+)2(BSNDI2–) (2), and (NH4+)2(BSNDI2–) (3), and their redox behaviors, thermal stabilities, crystal structures, electron transport properties, and dielectric constants were compared to those of neutral bis(phenyl)–naphthalenediimide (4). Crystals 1, 2, and 3 had quite high thermal stabilities up to 850, 810, and 600 K, respectively, even though organic molecules. A two-dimensional (2D) n-type electron transport layer consisting of NDI π cores was sandwiched between networks of highly polarized electrostatic cation–anion pairs showing 2D herringbone (1), one-dimensional π-stacking (2), and brickstone-like 2D π-stacking (3) interactions. The values of electron mobility in polycrystalline 1, 2, 3, and 4 reached 0.22, >0....