A novel layered lithium niobium titanate as battery anode material: Crystal structure and charge-discharge properties
| Autor: | Claudio Maria Mari, Ilya Pinus, Riccardo Ruffo, Michele Catti, Matteo M. Salamone |
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| Přispěvatelé: | Catti, M, Pinus, I, Ruffo, R, Salamone, M, Mari, C |
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
Materials science
Neutron diffraction Niobium chemistry.chemical_element Mineralogy 02 engineering and technology Crystal structure engineering.material Anode material 010402 general chemistry 01 natural sciences LiTi LiTi2NbO7 Lithium ion batterie General Materials Science Spinel Chemistry (all) General Chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics Titanate 0104 chemical sciences Crystallography chemistry NbO engineering Lithium Orthorhombic crystal system Materials Science (all) 0210 nano-technology Monoclinic crystal system |
| Popis: | LiTi 2 NbO 7 was synthesized from CsTi 2 NbO 7 by direct Cs + /Li + ion exchange and subsequent thermal decomposition of the hydrated form. Neutron powder diffraction data were collected at high-resolution (ILL, France) and analyzed by Rietveld refinements and Fourier difference techniques, revealing a layer-like crystal structure (orthorhombic Pbnm , a = 9.2476(6), b = 16.955(2), c = 3.7542(2) A) partly similar to that of monoclinic LiTi 3 O 7 . Lithium is tetrahedrically coordinated and bridges adjacent layers of (Ti,Nb)O 6 octahedra. Nb atoms are strongly ordered in one of the three independent sites available for Ti/Nb, thus compensating for the unbalance of negative charge from the surrounding O atoms. Electrochemical measurements were performed on a LiTi 2 NbO 7 electrode vs. Li/Li + couple. Overlapping Ti 4 + /Ti 3 + and Nb 5 + /Nb 4 + redox processes occur around 1.4 V, with a specific charge of 245 mAh/g (about 2.8 electrons per f.u.) in the 2.30 to 1.15 V range. Charge-discharge cycling results show a reversible and stable specific capacity of 220 mAh/g at low current density, indicating that this material is a promising alternative to Li 4 Ti 5 O 12 spinel for reversible anode applications in lithium batteries. |
| Databáze: | OpenAIRE |
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