Nickel selenide nano-cubes anchored on cadmium selenide nanoparticles: First-ever designed as electrode material for advanced hybrid energy storage applications

Abstract

The rational design and impressive performance of the desired electrode material are one of the top priorities in the field of the supercapacitor era. Chalcogenides are functional materials that attracted tremendous research due to their great electrochemical activity, non-toxicity, high theoretical capacities, low cost, high environmental safety, and tunable electronic configurations. Combining two different materials (compositing strategy) is a popular route to develop novel, robust, and highly efficient electrodes for high capacity, energy, and power delivery with good durability. Herein, for the first time, a high-performance hybrid supercapacitor is developed based on NiSe2, and CdSe and their composites, e.g., NiSe2/CdSe (denoted as CN-1, CN-2, and CN-3) via hydrothermal via ex-situ wet-chemical method. By changing the stoichiometry of the host compounds (e.g., NiSe2, CdSe), various nanocomposites take birth, such as; CN-1, CN-2, and CN-3. Notably, their capacitive performance was measured and compared in an aqueous alkaline media in KOH with three milli molar concentration. Subsequently, the CN-2 electrode displayed a good electrochemical energy storage performance of 358C/g capacity and lower overall resistance, which promotes the fast diffusion of electrolyte kinetics; hence, optimized electrochemical properties prove its importance for the fabrication of full cell development. More strikingly, the CN-2//AC hybrid supercapacitor revealed a high capacitance of 90 F/g, 40.5 Wh/kg energy density, and a maximum power of 7161.2 W/kg coupled with a high stability of 87.6 % (20 A/g) when repeatedly tested for long-term 15,000 cycling. The proposed method portrays a cost-effective and appealing runner for high-energy hybrid supercapacitors in future energy storage applications.