Interfacial Deposition of Three-Dimensional Nickel Hydroxide Nanosheet-Graphene Aerogel on Ni Wire for Flexible Fiber Asymmetric Supercapacitors

Burgeoning interest in flexible and wearable electronics sparks the rapid development of flexible fiber-shape supercapacitors (SCs). Herein, three-dimensional porous reduced graphene oxide (RGO) aerogel is deposited on flexible Ni wire via a simple aqueous reduction method. RGO aerogel exhibits good capacitive performance, thanks to its unique porous structure and good electrical conductivity. In order to fabricate an asymmetric SC, nickel hydroxide nanosheets are controllably deposited on the RGO sheets as the positive electrode while the RGO aerogel coated Ni wire is used as negative one. The obtained flexible fiber SCs exhibit good performance with high power/energy densities (10.3 kW kg(-1)/3430 mW cm(-3), 24.5 Wh kg(-1)/0.83 mWh cm(-3)) and good cycling stability (83% retention, even after 6000 cycles). The solid-state nature combined with good flexibility makes the fiber SCs attractive for energy storage applications in portable and wearable electronics. The interfacial deposition of reduced graphene oxide and nickel hydroxide on Ni wire renders the fabrication of flexible fiber asymmetric supercapacitors for sustainable energy storage.