Interface guide: In-situ integrating MoS2 nanosheets into highly ordered polypyrrole film for high performance flexible supercapacitor electrodes

Abstract Self-standing film with desirable properties is a promising candidate for flexible electronic applications. Conducting polymers (CP) have intrinsic film forming and pseudocapacitive characteristics. However, pure CP films are rarely applied in energy storage devices due to their disordered molecular structure which would result in insufficient utilization of the supported active materials and apparent volumetric effect. The specific lamellar structure of 2D nanosheets is an ideal platform for CP growing into self-standing film with desirable structure. Herein, a facile interface engineering strategy is proposed for in-situ integrating 2D MoS2 nanosheets into 3D polypyrrole (PPy) framework, in which dodecylbenzene sulfonate (DBS−) anions intercalate into MoS2 nanosheets and guide PPy to grow into ordered molecular structure. The resultant self-standing films with PPy chains in a high degree of ordering can deliver a high area capacitance of 1200 mF/cm2 and a high volumetric capacitance of 325 F/cm3, which are significantly superior to pure PPy films and show a great potential for high performance flexible supercapacitor application.