Role of Carbon Nanotube for Flexible Supercapacitor Application

In this current era, with the ever-increasing demand for portable and wearable energy storage devices, the supercapacitor (SC) plays a very positive role to fulfill this gap. Carbon nanotubes (CNTs) are extremely promising material candidate in flexible SC where it works as an electrode to enhance the energy and power densities of the SC because of their remarkable mechanical property, high electrical conductivity, large surface area, and ease to functionalize. Moreover, CNTs can assemble into various macroscopic structures with different dimensions such as single-wall CNTs (SWCNTs), double-wall CNTs (DWCNTs), and multi-wall CNTs (MWCNTs). In this book chapter, a comprehensive discussion on the synthesis, characterization and further utilization of CNTs in metal oxide-based SC has been outlined. Here, the metal oxide can be 1D nanofibers, 2D thin films, and 3D aerogels. Further, a detailed study has been framed on the design methodology and fabrication techniques for the supercapacitor. Recently, various developments and state-of-the-art applications have been proposed for such structures wherein CNTs have been used as electrodes in flexible SCs with varied device configurations such as sandwiched and interdigital in-plane. Furthermore, the flexible CNT-based electrodes have shown great bendability, and compressibility, as well as a long cycle lifetime.