In situ synthesis of advantageously united copper stannate nanoparticles for a new high powered supercapacitor electrode

In this study, we demonstrate the design and fabrication of a novel flexible nanoarchitecture by facile coating ultrathin copper stannate nanoparticles (Cu2SnO4 NPs) grown radially on nickel foam (NF) to achieve a high specific capacitance, high-energy density, high-power density, and long-term life for supercapacitor electrode applications. The structural and morphological properties of the material were characterized using different techniques. The Cu2SnO4 NPs were used as the active electrode material for supercapacitor applications. The electrochemical properties of the Cu2SnO4 NPs as a binder-free electrode for a supercapacitor were examined using cyclic voltammetry (CV), galvanostatic charge and discharge analysis (GCD), electrochemical impedance spectroscopy (EIS), and cycle life measurements in 2 M KOH electrolyte. The GCD analysis exhibited a specific capacitance as high as 2329.68 F g(-1) at 1 A g(-1) and a good rate capability (1330 F g(-1) at 70 A g(-1)). Moreover, this approach also offers an exceptionally high area-normalized capacitance of 4.66 F cm(-2). This capacitor electrode has excellent cyclic stability with 91.4% capacitance retention after 3000 cycles at 20 A g(-1), together with 99.2% Coulomb efficiency in a three-electrode system. The superior electrochemical performance of the Cu2SnO4 NPs/NF composites is attributed to the synergistic effects of the hierarchical porosity, Cu2SnO4 NPs, and 3D nickel foam network structure, which can effectively accommodate the huge volume change of the Cu2SnO4 nanoparticles during cycling and maintain perfect electrical conductivity throughout the electrode. Furthermore, the asymmetric supercapacitors (ASCs) based on the as-obtained Cu2SnO4 NPs cathode and activated carbon (AC) anode displayed an excellent electrochemical behavior with a high energy density of 91.04 W h kg(-1) at 4.35 kW kg(-1) and superior cyclic stability. It also shows a small leakage current. Furthermore, the SC device retains 1.1 V of its initial voltage (1.4 V) after the 8 h self-discharge test, which suggests the good state of health of the SC device. These results demonstrate that Cu2SnO4 NPs could be a promising electrode for high-performance energy storage devices.

Automated summary

This study demonstrates the design and fabrication of a novel flexible nanoarchitecture using ultrathin copper stannate nanoparticles on nickel foam to achieve high-performance supercapacitor electrodes. The nanostructure exhibits high specific capacitance, energy density, power density, and long-term stability. The electrochemical performance is attributed to the hierarchical porosity, Cu2SnO4 nanoparticles, and 3D nickel foam structure.