Influence of the carbonaceous conductive network on the electrochemical performance of ZnFe2O4 nanoparticles

Herein, the influence of the carbon precursor used for the realization of carbonaceous percolating network incorporating ZnFe2O4 is investigated. Three different precursors, namely sucrose (Suc), citric acid (CA), and oleic acid (OLEA) were used for the realization of such carbonaceous matrix. The composite materials were characterized by means of thermogravimetric analysis (TGA), gas adsorption using the BET isotherm, Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Electrodes based on the resulting composite materials were investigated, performing electrochemical impedance spectroscopy and galvanostatic cycling. The results showed that the homogeneity of the carbon coating rather than the absolute amount of carbon enhanced the electrochemical performance of ZnFe2O4 nanoparticles. The most advantageous coating properties were obtained with sucrose as carbon precursor, obtaining a highly stable specific capacity higher than 1000 mAh g(-1) for more than 60 cycles. (C) 2013 Elsevier B.V. All rights reserved.