Synthesis and characterization of porous carbon materials modified with NIFe 2 O 4 for applications in lithium-ion batteries

Abstract

The present energetic situation is in a transition process that involves leaving fossil fuel as an energy resource to employ a more friendly environmentally one. To that end, it is necessary to improve the current methods of energy-storing and working in their development. Li-Ion batteries are one of the most promising ways of energy storage. In this work, we focus to improve the performance of such systems by modifying the active material in the anode. In particular, we researched about ordered mesoporous structured carbons functionalized with NiFe2O4.With the aforementioned objective, it was started by synthesizing employing the sol-gel method [1], a matrix of ordered pores of silicon oxide (SBA-15). From which, after successive impregnations with sucrose and calcination in an inert atmosphere, a porous carbon matrix CMK-3 was obtained. These highly ordered two-dimensional porous materials have a uniform pore diameter, large surface area and remarkable thermal and electrical conductivity [2, 3]. The use of these materials as anodes in lithiumion batteries led to a significant increase in the conduction of both lithium ions and electrons [4].The carbon materials were modified with a NiFe2O4 spinel, using the wet impregnation method. The use of this spinel is grounded on the fact that it has a high theoretical capacity (915mAh/g) and that both Ni and Fe are low-cost and abundant elements (which is important for the possible applicability to the industry) [5]. The resulting materials were characterized by the following techniques: Low and high angle x-ray diffraction (DRX), scanning and transmission electron microscopy (SEM and TEM), elemental analysis (EDX), nitrogen adsorption isothermal analysis with BET model, ultraviolet-Visible diffuse reflectance spectroscopy (UV-vis), programmed temperature reduction (TPR), X-Ray emitted photoelectron spectroscopy (XPS) and galvanostatic cycling of electrochemical cells.