Flexible polyester yarn/Au/conductive metal-organic framework composites for yarn-shaped supercapacitors

摘要

One-dimensional (1D) flexible yarn-shaped supercapacitors are highly desirable for future wearable electronics by virtue of small volume, lightweight, portability and knittability. Conductive metal-organic frameworks (MOFs) are considered as promising electrode materials in supercapacitors, owing to their high porosity, tunable chemical structure, specific surface area and good electrical conductivity. In this work, Ni-3(2,3,6,7,10,11-hexahydroxytriphenylene)(2) (Ni3HHTP2), a conductive MOF, is fully coated on the surface of Au-plated polyester yarn (PET/Au) to boost the electrochemical performance. The assembled all-solid-state symmetrical yarn supercapacitor which is fabricated by a facile dip-coating method exhibits a high length capacitance of 113.6mF/cm at a current density of 0.1 mA/cm, with an energy density of 3.94 mu Wh/cm (at 24.97 mu W/cm), a power density of 0.25 mW/cm (at 0.594 mu Wh/cm). Such a yarn supercapacitor also demonstrates extremely stable electrochemical performance under the mechanical bending and stretching conditions. Therefore, the high-performance yarn supercapacitor is a promising energy storage device for wearable electronic applications.