Enhanced dielectric properties of poly(arylene ether nitrile) composite films employing MoS2-based semiconductors for organic film capacitor applications

Abstract

Polymer-based dielectric composites are potential substitute dielectrics for organic thin film capacitors. In this work, the exfoliated molybdenum disulfide (MoS2) was functionalized by mussel-inspired poly(dopamine) (PDA) to form core-shell structured composites (MoS2@PDA) under easy-handling and eco-friendly conditions, and then as filler incorporated into poly(arylene ether nitrile) (PEN) matrix. The interfacial interaction and dispersion of MoS2@PDA in PEN matrix were improved by the strong adhesion of PDA interlayer to exfoliated MoS2, π-π conjugation and hydrogen bond interactions, which formed by the polar nitrile group of PEN and catechol groups of PDA. Therefore, the PEN/MoS2@PDA composite films exhibited enhanced dielectric constant, synchronously maintaining better flexibility, thermal stability and the same level of dielectric loss with PEN. Particularly, the addition of 20 wt% MoS2@PDA into PEN matrix leaded to substantial growth of dielectric constant up to 12.9 at 1 kHz, while the PEN matrix was just 4.2. Meanwhile, the dielectric composites maintained relatively low dielectric loss of 0.022 at 1 kHz, which was ascribed to the improved compatibility and interfacial interaction between filler and PEN. All in all, a eco-friendly and easy-handling strategy was provided to tune the dielectric constant and dielectric loss of semiconductor/polymer composites, which has great potential to promote the development of dielectric in the fields of organic thin film capacitors.