Surface Modification of Commercial Cotton Yarn as Electrode for Construction of Flexible Fiber-Shaped Supercapacitor

In this study, we report on the rational design and facile preparation of a cotton-reduced graphene oxide-silver nanoparticle (cotton-RGO-AgNP) hybrid fiber as an electrode for the building of a flexible fiber-shaped supercapacitor (FSSC). It was adequately characterized and found to possess a well-defined core-shell structure with cotton yarn as a core and a porous RGO-AgNP coating as a shell. Thanks to the unique morphological features and low electrical resistance (only 2.3 omega center dot cm(-1)), it displayed attractive supercapacitive properties. When evaluated in a three-electrode setup, this FSSC electrode delivered the highest linear and volumetric specific capacitance of up to ca. 12.09 mF center dot cm(-1) and ca. 9.67 F center dot cm(-3) with a satisfactory rate capability as well as a decent cycling stability. On the other hand, an individual parallel symmetric FSSC cell constructed by this composite fiber fulfilled the largest linear and volumetric specific capacitance of ca. 1.67 mF center dot cm(-1) and ca. 0.67 F center dot cm(-3) and offered the maximum energy density, as high as ca. 93.1 mu Wh center dot cm(-3), which outperformed a great number of graphene- and textile yarn-based FSSCs. Impressively, bending deformation brought about quite a limited effect on its electrochemical behaviors and almost no capacitance degradation took place during the consecutive charge/discharge test for over 10,000 cycles. Consequently, these remarkable performances suggest that the currently developed cotton-RGO-AgNP fiber has considerable application potential in flexible, portable and wearable electronics.

Automated summary

This study presents a cotton-RGO-AgNP hybrid fiber electrode for flexible fiber-shaped supercapacitors (FSSCs) with well-defined core-shell structure and excellent supercapacitive properties. The electrode exhibited high specific capacitance, rate capability, cycling stability, and energy density, outperforming many other graphene- and textile yarn-based FSSCs. It also showed remarkable electrochemical behavior under bending deformation and long-term cycling tests, indicating its significant potential for flexible and wearable electronics applications.