Synthesis of ZnFe2O4 nanoparticles with high specific surface area for high-performance supercapacitor

The specific surface area is an important parameter influencing the storage capability of materials due to its direct effect on the reaction sites availability. In this study, ZnFe2O4 nanoparticles with a high specific surface area, 78.9 m(2) g(-1), were prepared by a weak ultrasonic irradiation technique. Fe(NO3)(3)center dot 9H(2)O, Zn(NO3)(2)center dot 6H(2)O and glucose were used as reagents and the prepared precursor was calcined in the air at 400 degrees C for 3 h. The product was characterized by thermogravimetric analysis, Fourier transform infrared, Raman spectra, X-ray diffraction, Brunauer-Emmett-Teller, Scanning electron microscopy as well as Transmission electron microscopy. The charge storage ability, cycling stability, and ion transport of the produced ZnFe2O4 nanoparticles were examined by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy tests in 1, 3 and 6 M KOH solutions. The highest specific capacitance of the ZnFe2O4 nanoparticles was obtained 712 F g(-1) at the scan rate of 2 mV s(-1) in 6 M KOH electrolyte, and the capacity retention for ZnFe2O4 nanoparticles was still maintained after 2000 cycles at 92.4, 94.2 and 96.6% in 1, 3 and 6 M KOH electrolytes, respectively.