Core-shell structure of Co₃O₄@CdS for high performance electrochemical supercapacitor

Core-shell nanostructures of Co₃O₄@CdS were synthesized on nickel foam using a facile, economical, scalable, and one pot hydrothermal method and a successive ionic layer adsorption and reaction (SILAR) method. The synergistic effects arising due to the hexagonal Co₃O₄ sheets and CdS nanostructures were assessed for potential electrochemical energy storage applications. The effects of the CdS SILAR coating cycles were examined by varying the number of cycles from 2 to 10. The Co₃O₄@CdS core-shell electrode exhibited a high specific capacitance of 1539 Fg⁻¹ (1385 Cg⁻¹) and 1322 Fg⁻¹ (1189 Cg⁻¹) at 10 mVs⁻¹ and 30 mA, respectively, with 98.5% capacitance retention after 2000 cycles. In addition, the Co₃O₄@CdS core shell nanostructure-based symmetric supercapacitor displayed excellent capacitive characteristics with a specific capacitance of 360 Fg⁻¹ (288 Cg⁻¹) and 99 Fg⁻¹ (79 Cg⁻¹) at 10 mVs⁻¹ and 10 mA, respectively, and 92% capacitance retention after 2000 cycles.