3D copper sulfide (Cu₂S) with different morphologies for high performance supercapacitors were synthesized via a simple, cost effective successive ionic layer adsorption and reaction (SILAR) method. Further, these Cu₂S nanostructure demonstrate excellent surface properties like uniform surface morphology, large surface area of Cu₂S samples. X-ray diffraction (XRD) X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy of these samples confirmed the crystallinity and crystal structure of Cu₂S. The electrochemical studies of Cu₂S samples have been investigated by cyclic voltammetry, charge–discharge and electrochemical impedance spectroscopy techniques. The maximum specific capacitance of flower-like and integrated nanotubes samples are found 761 and 470 F g⁻¹, respectively, at a scan rate of 5 mV s⁻¹. The electrodes are prepared using a simple four-beaker SILAR system at ambient conditions, thus providing an easy approach to fabricate high-power and high-energy supercapacitors. Further, EIS analysis shows a lower ESR value, high power performance, excellent rate as well as frequency response to flower-like Cu₂S sample. The Ragone plot shows better power and energy densities of all Cu₂S nanostructured samples. The long-term cycling performance of Cu₂S is examined with excellent retention of 95%. The high surface area provided by the porous and more conductive 3D nickel foam have been utilized properly to enhance the electrochemical properties of copper sulfides with charge transport and storage.

A cinnamon-like La₂Te₃ nanostructure has been prepared by a simple chemical bath deposition (CBD) route. Field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy techniques have been used to characterize the morphological and structural properties of the La₂Te₃ thin films. The prepared La₂Te₃ thin film electrodes are applied in a supercapacitor, in which they exhibited a high specific capacitance value of 469 F g⁻¹ at a scan rate of 2 mV s⁻¹ with an excellent cycling performance up to 1000 cycles. Even at a specific power of 2.5 kW kg⁻¹, the La₂Te₃ electrode possessed a specific energy of ∼126 Wh kg⁻¹. At a relatively high discharge current density of 4 mA cm⁻², the specific capacitance was still maintained at 220 F g⁻¹. Furthermore, portable La₂Te₃ asymmetric supercapacitor devices have been fabricated using an aqueous 1 M KOH electrolyte with good specific energy and specific power. Such an impressive portable asymmetric supercapacitor is a promising candidate for applications in high-performance energy storage systems.