Growth of Film Electrodes through Electrospray Coating of Precursor Sol for Use in Asymmetric Supercapacitor

Abstract

Nanoparticulate films of NiO and carbon are fabricated by electrospray coating of respective aqueous precursors on Ni foam. The adhesion of the active layers to the substrate during solvent evaporation, calcination, or carbonization is demonstrated for both types of electrodes. The effect of metal precursor composition and calcination temperature is analyzed through X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical techniques. The capacitance of NiO and carbon film electrodes is found to be 343 mF cm–2 (286 F g–1) and 118 mF cm–2 (118 F g–1), respectively at a current density of 1 mA cm–2. The supercapacitor in an asymmetric setup delivers specific energy and specific power to the levels of 12.6 Wh kg–1 and 1.7 kW kg–1 respectively, with the capacitance retention of 88% after 2000 cycles at 5 mA cm–2.

Critical Review on Synthetic Routes and Catalytic Applications of Hollow Nanomaterials

“…[108] Zang et al obtained multishell structure carbon hollow sphere with foam like cores against silica template which were already coated with RF in addition to second layer of silica (SiO2@RF@SiO2). [109] This carbonized outcome obtained in the presence of nitrogen gas. Multi shell structures could obtain through repeat coating and templating.…”

Carbon Dot-Regulated 2D MXene Films with High Volumetric Capacitance

“…Ever-growing demands for flexible and wearable electronics have led to tremendous exploration to develop flexible, light-weight, high-performance supercapacitors. , Construction of advanced electrode materials with superb flexibility and high volumetric capacitances has been regarded as one of the most promising methods. − The most widely used carbonous materials, such as porous carbon and a carbon nanotube, are considered as the predominant choice of electrode materials but limited by their low volumetric capacitances, which are attributed to the inherent energy storage mechanism and low density. ,− An emerging family of two-dimensional (2D) materials, MXenes, holds great promise in energy storage applications with a high volumetric capacitance that could be ascribed to their unparalleled properties of metallic conductivity, hydrophilicity, high density, and easy to fabricate binder-free electrodes. − Additionally, they are also emerging as potential candidates as pseudocapacitive electrode materials in acidic aqueous electrolytes. , …”