Enhanced performance of SnO2-C composite fibers containing NiO as lithium-ion battery anodes

SnO2-C fibers containing NiO (SnO2-NiO-C fibers) were synthesized by an electrospinning technique with subsequent calcination in an inert atmosphere using tin(II)2-ethylhexanoate and nickel acetate as starting materials. X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and thermogravimetrical analysis (TGA) were employed to characterize the as-obtained composite fibers, and electrochemical tests, including galvanostatic charge discharge and cyclic voltammetry (CV), were conducted to measure their electrochemical performance. The SnO2-NiO-C fibers were comprised of ultrafine particles of 1-2 nm size with poor crystallinity encapsulated in an amorphous carbon matrix, and a low-density of distribution nano-particles with a size of similar to 50 nm were observed on the fibers surfaces. The SnO2-NiO-C fibers retain their capacity very well, and their reversible specific capacity is 60-110 mA h g(-1), which is higher than that of SnO2-C fibers, at a current density of 50 mA g(-1) with a voltage range of 0.01-3.00 V. Their excellent electrochemical performance is ascribed to their one dimensional (1D) structure with metal oxide particles embedded in a carbon matrix, and the synergistic effects of SnO2 and NiO. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.