Metal organic framework-derived cobalt telluride-carbon porous structured composites for high-performance supercapacitor

Abstract: Porous nanostructured composites are emerging electrode materials for energy storage devices. This work reports the fabrication of metal-organic framework (MOF)-derived cobalt telluride-carbon porous structured composite on nickel foam (CoTe@C–NiF) as electrodes for supercapacitor. The CoTe@C–NiF electrode can store charge in different potential regions of 0 to 0.5 V as positive and −0.8 to 0 V as negative electrodes. Benefitting from its bifunctional charge storage property, the CoTe@C–NiF, when employed as electrodes in a symmetric supercapacitor, produces an optimum output voltage of 1.45 V in aqueous alkaline electrolyte, resulting in an energy density of 43.84 Wh Kg⁻¹ at a power density of 738.88 W kg⁻¹, and retains 21.95 Wh Kg⁻¹ even at the high power density of 6173.44 W kg⁻¹. Moreover, the CoTe@C–NiF is reproducible via a large-scalable and straightforward synthesis protocol, comprising two-steps, followed by an annealing process at 400 °C in argon. The results suggest that the CoTe@C–NiF is a promising electrode material for high-performance symmetric supercapacitor.