Fabrication of spinel CuNiMn2O4 nanoparticles encapsulated with g-C3N4 nanosheets for bifunctional sensor and energy storage applications

Abstract

Worldwide, the sensor and energy storage field is most popular due to its demand for usage and increased economic value. For this purpose, it is emergent to prepare an electrode material for both the application point of view. This work describes a Mn based spinel structure of CuNiMn₂O₄ (CNM) is prepared by the solvothermal method and to enhance its electrochemical property, 1 and 3 % of g-C₃N₄ is incorporated into the (CNM) as a nanocomposite of (CNM@1 % G) and (CNM@3 % G) formation. The incorporation of g-C₃N₄ into the CNM, the internal resistance is decreased, which is the reason for the enhancement of the electrochemical properties. The systematic characterizations studies of XRD, FESEM, HRTEM, and XPS are investigated and electrochemical studies of cyclic voltametry, electrochemical impedance analysis, Chronoamperometry, galvanostatic charge discharge studies are performed for a non-enzymatic glucose detection and for supercapacitor application. The FESEM reveals the nano flake like particle morphology and HRTEM reveals the nanoflake like morphology. The CNM@3 % G nanocomposite obtained a higher sensitivity and LOD of 1268 mA µM⁻¹ Cm⁻² and 0.305 µM. For the supercapacitor application of three electrode system, the CNM@3 % G nanocomposite is obtained a higher specific capacitance of 195 F/g for 1 A/g of current density. For a two electrode system, the calculated specific capacitance is 13 F/g for 4 A/g of current density. The calculated energy and power density are 4.06 Wh kg⁻¹ and 235 kW kg⁻¹. The obtained coulombic efficiency is 100 % and stability was determined as 2500 cycles.