Eu-ZnCo2O4 nanoflower structures prepared by sol-gel method for high-performance supercapacitor applications

In this study, Eu-doped ZnCo2O4 with nano-flower-like structures and varying doping ratios was synthesized using the sol-gel method. Electrochemical characterization was performed to investigate the impact of Eu doping on the structural and electrochemical properties of ZnCo2O4 materials. The results demonstrate that among different doping conditions, the sample doped for 10 h with a Eu content of 0.4% exhibits superior electrochemical performance. At a current density of 3 A/g, it achieves a specific capacitance of 1750 F/g. After 10,000 cycles, the specific capacitance remains at 1715 F/g, retaining 98% of its initial value, indicating excellent cycling stability and durability. In comparison, CNTs (SW) exhibit a specific capacitance of 285 F/g after 5000 cycles, which is 92.5% of their initial value (259 F/g), highlighting their good cycling stability. For the 0.4% Eu-ZnCo2O4//CNTs asymmetric device, at a current density of 1 A/g, the initial specific capacitance is 150 F/g, and after 10,000 charge-discharge cycles, it retains 90% of its initial value. Under a current density of 1 A/g and a potential window of 1.2 V, the device achieves an energy density of 100 Wh/kg and a power density of 8000 W/kg. These findings not only validate the effectiveness of the Eu doping strategy but also provide new insights into the development of high-performance energy storage systems and environmentally friendly applications, paving the way for future research and practical implementation.