Tantalum Oxide/CNF as a Electrocatalyst for Rechargeable Li-Air Battery with Long-Cycle Stability

초록

Abstract. Lithium-air batteries have attracted considerable interest as a candidate for the most reliable energy storage systems such as portable electronic devices and hybrid electric vehicles (HEVs) owing to its high specific energy density compared with lithium ion battery. However, in spite of current efforts for practical applications, the maintenance of high electrolyte stability, low charge-discharge overpotential, and degradation of electrodes are the obstacles to be overcome for commercialization. In order to achieve a cell with high activity and stability for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), development of an effective electrocatalyst is strongly needed. In this study, TaOx/CNFs was simply synthesized using sputtering method, and was employed as an air cathode for a Li-air battery. The surface morphology was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. The structure and surface compositions of prepared electrodes were examined by X-ray diffraction (XRD), energy dispersive spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS). Total amounts of TaOx in samples were determined by thermogravimetric analysis (TGA). The electrochemical characterizations were conducted using a Swagelok-type cell in oxygen atmosphere.