High-performance symmetric supercapacitor based on activated carbon-decorated nickel diselenide nanospheres

Abstract

The vital challenge is to advance the electronic conductivity of the transition metal diselenide for their supercapacitor application. In this report, nickel diselenide nanospheres and their decoration by activated carbon are reported by a one-step, surfactant-free hydrothermal technique. The activated carbon-decorated NiSe2 nanospheres (NAC) electrode displays high electrochemical performance than pure NiSe2 nanospheres due to more active sites, enhanced conductivity, and reduced diffusion path of electrons and electrolyte ions for maximum energy storage. The NAC electrode depicts a specific capacity of about 119 C g?1 at 0.3 A g?1. The fabricated symmetric supercapacitor using an NAC electrode shows a high specific capacitance of about 282 F g?1 at 10�mV�s?1. The cycle stability of 70% for ten thousand cycles is exhibited for the fabricated symmetric supercapacitor. It manifests high specific energy of 28�W�h�kg?1 and specific power of value 980�W�kg?1 at 1 A g?1. Device applicability with load is tested at laboratory scale by glowing different color LEDs, and a panel of 26 red LEDs illuminated for 56�min effortlessly. A self-explanatory mechanism has also been proposed to make it easier to realize the readers about glowing LEDs, and their panels. � 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.