Clay-assisted hierarchical growth of metal-telluride nanostructures as an anode material for hybrid supercapacitors

Exploring a novel electrode material with a rational composition/nanostructure design is a general strategy to fabricate the high-performance electrodes for supercapacitors (SCs). Clay mineral materials including montmorillonite are potential electrode materials owing to their inherently porous structure, high specific surface area, and environmental friendliness. Nevertheless, low electronic conductivity limits the application of montmorillonite alone as a high-performance electrode for SCs. Thus, it is essential to improve the surface conductivity by additional modification with metal sources. In this work, an advanced battery-type electrode is suggested based on montmorillonite as a template to enable the hierarchical growth of nickel telluride (NiTe) nanostructures with considerable porosity. Given their abundant micro-porous structure and high specific surface area, different compositions have been employed by varying the Ni and Te contents to understand the effect of coordination on electrochemical performance. It was found that the optimized composition of montmorillonite-based micro-nanostructure with 75% Ni and 25% Te (C-MN0.75T0.25) improves the specific surface area, allowing easy adsorption/desorption of electrolytic ions. With a high specific capacity, superior electrochemical performance was successfully demonstrated in a three-electrode configuration. Additionally, the assembled hybrid supercapacitor (HSC) device along with a capacitive-type electrode possessed excellent capacitance, long-term endurance, high energy, and power densities, exhibiting the desired properties of an energy storage system. This study paves the way toward the development of simple and low-cost clay-based electrodes for energy storage applications. [Display omitted] •C-MNT was synthesized by oven-based wet chemical method.•Novel nanostructure engineering was used to improve the specific surface area.•C-MNT exhibits significant potential for high performance electrochemical device.