Abstract
Hierarchical nanostructures with appropriate morphology and surface functionalities are highly desired to achieve an optimized electrochemical property for active electrode materials. This work renders the facile hydrothermal synthesis of CdO, SnO2, and CdO–SnO2 nanocomposite, and their capacitive performance was tested. The formation of the pure samples and their composite was committed by low-temperature Raman spectroscopy and x-ray diffraction studies which revealed the tetragonal and cubic structures of CdO and SnO2 powder samples with good crystallinity and purity. The morphological postmortem reveals the formation of nanoparticles morphology of CdO with a highly smooth surface appearance. Besides, the SnO2 illustrates the morphology of the micro flowers composed of ultrathin nanosheets. More specifically, the electrochemical properties indicate the pseudocapacitive charge storage mechanism based on cyclic voltammetry and chronopotentiometry analysis. The CdO–SnO2 composite electrode displayed a higher capacitance due to additional pores/space offered for active sites and continuously allowed electrolyte ions to interact with the inner/outer surface of the electrode. These exciting findings led us to design and fabricate battery hybrid supercapacitors (BHSC) from CdO–SnO2, and activated carbon (AC), referred to as CdO–SnO2//AC BHSC, attains a high power delivery (5717 W/kg), and a maximum energy density of 42 Wh/kg at low discharge rate. Noteworthy, a stable cycling performance was obtained with only 91.3% retention after 8000 cycling at a large discharge current of 10 A/g, denoting the magnificent durability of the active electrode material.
CdO nanoparticles with SnO2 flakes morphology constructed via a 0D/2D architecture were prepared via the sol-gel method for hybrid supercapacitors for the first time, which delivers high cycling stability, superior energy density, and power delivery. [Display omitted]
•CdO nanoparticles with SnO2 flakes morphology combined with 0D/2D architecture was prepared via sol-gel method for hybrid supercapacitors.•A CdO–SnO2 nanocomposite displayed a significantly enhanced capacitance 383 F/g than its bulk counterparts.•A CdO–SnO2.||AC HSC exhibits a high cycling durability with superior energy 42 Wh/kg and power delivery of 5717 W/kg.