Scalable CNTs/NiCoSe₂ Hybrid Films for Flexible All-Solid-State Asymmetric Supercapacitors

Abstract

The rapidly developing wearable flexible electronics makes the development of high-performance flexible energy storage devices, such as all-solid-state supercapacitors (SCs), particularly important. Herein, we report the fabrication of CNTs/NiCoSe₂ hybrid films on carbon cloth (CC) through a facile co-electrodeposition method based on flexible electrodes for all-solid-state SCs. The NiCoSe₂ sheets grown on CNTs uniformly with a diameter of 50-100 nm act as the active materials. The CNTs in the hybrid films act as the scaffold to offer more deposition sites for NiCoSe₂ and provide a conductive network to facilitate the transfer of electrons. Moreover, the one-step electrodeposition process avoids the usage of any organic binders. Benefiting from the high intrinsic reactivity and unique 3D architecture, the obtained CNTs/NiCoSe₂ electrode delivers high specific capacity (218.1 mA h g^-1) and satisfactory durability (over 5000 cycles). Remarkably, the CNTs/NiCoSe₂//AC flexible all-solid-state (FASS) ASC provides remarkable energy density (112.2 W h kg^-1) within 0-1.7 V and maintains 98.1% of its initial capacity after 10,000 cycles. In addition, this flexible ASC device could be fabricated at a large scale (5 × 6 cm²), and the LED arrays (>3.7 V) can be easily lighted up by three ASCs in series, showing its potential practical application.