Waste-Cotton-Cloth-Derived Sustainable and Flexible High-Performance Supercapacitor

Turning waste cotton cloth into an energy-storage device kills two birds with one stone. It can reduce waste generation from textile industries and become a sustainable, low-cost, and readily available source of material to fulfill the global energy demand. Herein, we develop a high-performance flexible supercapacitor from waste cotton cloths. This involves a straightforward method for the fabrication of SnO2@carbon cloth (SnO2@CC) from waste cotton cloths. The fabricated SnO2@CC, having a high specific surface area (∼786 m2 g–1) with micropores (∼1.62 nm), was further used as a freestanding and binder-free electrode in the supercapacitor. The resulting supercapacitor exhibited an excellent specific capacitance of 1024.32 F g–1 at a current density of 0.5 A g–1 with outstanding long cycling stability (nearly 100% for 10000 cycles) in an aqueous 1 M Na2SO4 electrolyte in a three-electrode system. Further, the SnO2@CC electrode is integrated with a waste-cotton-cloth-based counter electrode and separator to fabricate asymmetric full-cell supercapacitor devices. The flexible asymmetric full-cell supercapacitor showed a promising electrochemical performance with an energy density of 18.9 Wh kg–1 and excellent mechanical stability.