Cobalt hydroxide [Co(OH)2] loaded carbon fiber flexible electrode for high performance supercapacitor

Abstract

Cobalt hydroxide nanoflakes are uniformly loaded on flexible carbon fiber (CF) paper, and provide good electrical connectivity to the current collector for use as supercapacitors. The unique porous nanostructure offers low ion diffusion and charge transfer resistance in the electrode. The effect of loading mass on electrochemical properties is investigated. The electrode with a mass loading of 2.5 mg cm⁻² shows the maximum specific capacitance of 386.5 F g⁻¹ at a current density of 1 mA cm⁻². Also the same electrode provides a good rate capability with energy and power densities of 133.5 W h kg⁻¹ and 1769 W kg⁻¹, respectively even at a higher current density of 10 mA cm⁻². The electrode reveals a cyclic stability of 92% over 2000 cycles. This kind of flexible, lightweight electrode could be effectively utilized for flexible supercapacitor fabrication, especially for wearable electronics.