Ali, Ghulam Lee, Ji-Hoon Oh, Si Hyoung Cho, Byung Won Nam, Kyung-Wan Chung, Kyung Yoon 2024-01-20T04:33:52Z 2024-01-20T04:33:52Z 2021-09-05 2016-03-09 1944-8244 https://pubs.kist.re.kr/handle/201004/124289 There is a significant interest to develop high-performance and cost-effective electrode materials for next-generation sodium ion batteries. Herein, we report a facile synthesis method for nanosized V2O5/C composite cathodes and their electrochemical performance as well as energy storage mechanism. The composite exhibits a discharge capacity of 255 mAh g(-1) at a current density of 0.05 C, which surpasses that of previously reported layered oxide materials. Furthermore, the electrode shows good rate capability; discharge capacity of 160 mAh g(-1) at a current density of 1 C. The reaction mechanism of V2O5 upon sodium insertion/extraction is investigated using ex situ X-ray diffraction (XRD) and synchrotron based near edge X-ray absorption fine structure (NEXAFS) spectroscopy. Ex situ XRD result of the fully discharged state reveals the appearance of NaV2O5 as a major phase with minor Na2V2O5 phase. Upon insertion of sodium into the array of parallel ladders of V2O5, it was confirmed that lattice parameter of c is increased by 9.09%, corresponding to the increase in the unit-cell volume of 9.2%. NEXAFS results suggest that the charge compensation during de/sodiation process accompanied by the reversible changes in the oxidation state of vanadium (V4+ <-> V5+). English American Chemical Society CORE-SHELL STRUCTURE ABSORPTION-SPECTROSCOPY VANADIUM-OXIDES HIGH-CAPACITY CARBON NANOCOMPOSITE Investigation of the Na Intercalation Mechanism into Nanosized V2O5/C Composite Cathode Material for Na-Ion Batteries Article 10.1021/acsami.5b11954 1 ACS Applied Materials & Interfaces, v.8, no.9, pp.6032 - 6039 ACS Applied Materials & Interfaces 8 9 6032 6039 scie scopus 000371945700032 2-s2.0-84960517032 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article CORE-SHELL STRUCTURE ABSORPTION-SPECTROSCOPY VANADIUM-OXIDES HIGH-CAPACITY CARBON NANOCOMPOSITE Na-ion batteries nanosized V2O5 NaV2O5 X-ray diffraction near-edge X-ray absorption fine structure