Preparation and electrochemical properties of nickel and cobalt selenides nanoparticles synthesized using one-pot synthesis method.

Hybrid electrochemical storage devices combining batteries and supercapacitors are essential for advancing energy storage technologies. Our study presents a simple one-pot synthesis method for nickel-cobalt selenide (NCSe) nanoparticles, optimizing selenium (Se) content to enhance microstructure, porosity, and electrochemical properties. NCSe nanoparticles with 1.8 mmol Se exhibited a remarkable specific capacity of 775 C g⁻1 at 1 A g⁻1 and 665 C g⁻1 with 85 % retention at 15 A g⁻1. An asymmetric supercapacitor using NCSe-1.8 mmol as the positive electrode and activated carbon as the negative electrode achieved 79 % retention after 2000 cycles at 15 A g⁻1. These findings underscore NCSe nanoparticles' potential as efficient electrode materials, advancing energy storage technologies. [ABSTRACT FROM AUTHOR]