Lithium Intercalation in Anatase Titanium Vacancies and the Role of Local Anionic Environment
- Sorbonne Univ., Paris (France). Physico-chimie des électrolytes et nano-systèmes interfaciaux, PHENIX; Tongji Univ., Shanghai (China). Inst. of New Energy for Vehicles, School of Materials Science and Engineering
- Sorbonne Univ., Paris (France). Physico-chimie des électrolytes et nano-systèmes interfaciaux, PHENIX
- Univ. of Bath, Bath (United Kingdom). Dept. of Chemistry
- PSL Research Univ., Paris (France). Inst. de Recherche de Chimie Paris (IRCP)
- CNRS-Univ. Paris Est, Thiais (France). Inst. de Chimie et des Matériaux Paris-Est
- Le Mans Univ.-CNRS, Le Mans (France). Inst. des Molécules et Matériaux du Mans
- Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS), X-ray Science Division
- Sorbonne Univ., Paris (France). Collège de France, Lab. de Chimie de la Matière Condensée de Paris; Réseau sur le Stockage Electrochimique de l’Energie (RS2E), Amiens (France)
- Sorbonne Univ., Paris (France). Physico-chimie des électrolytes et nano-systèmes interfaciaux, PHENIX; Réseau sur le Stockage Electrochimique de l’Energie (RS2E), Amiens (France)
The structure of bulk and nondefective compounds is generally described with crystal models built from well mastered techniques such the analysis of an X-ray diffractogram. The presence of defects, such as cationic vacancies, locally disrupt the long-range order, with the appearance of local structures with order extending only a few nanometers. To probe and describe the electrochemical properties of cation-deficient anatase, we investigated a series of materials having different concentrations of vacancies, i.e., Ti1–x–y$$\square$$x+yO2–4(x+y)F4x(OH)4y, and compared their properties with respect to defect-free stoichiometric anatase TiO2. At first, we characterized the series of materials Ti1–x–y$$\square$$x+yO2–4(x+y)F4x(OH)4y by means of pair distribution function (PDF), 19F nuclear magnetic resonance (NMR), Raman and X-ray photoelectron spectroscopies, to probe the compositional and structural features. Second, we characterized the insertion electrochemical properties vs metallic lithium where we emphasized the beneficial role of the vacancies on the cyclability of the electrode under high C-rate, with performances scaling with the concentration of vacancies. The improved properties were explained by the change of the lithium insertion mechanism due to the presence of the vacancies, which act as host sites and suppress the phase transition typically observed in pure TiO2, and further favor diffusive transport of lithium within the structure. NMR spectroscopy performed on lithiated samples provides evidence for the insertion of lithium in vacancies. By combining electrochemistry and DFT-calculations, we characterized the electrochemical signatures of the lithium insertion in the vacancies. Importantly, we found that the insertion voltage largely depends on the local anionic environment of the vacancy with a fluoride and hydroxide-rich environments, yielding high and low insertion voltages, respectively. Lastly, this work further supports the beneficial use of defects engineering in electrodes for batteries and provides new fundamental knowledge in the insertion chemistry of cationic vacancies as host sites.
- Research Organization:
- Argonne National Laboratory (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- AC02-06CH11357
- OSTI ID:
- 1484020
- Journal Information:
- Chemistry of Materials, Vol. 30, Issue 9; ISSN 0897-4756
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Rechargeable Aqueous Electrochromic Batteries Utilizing Ti‐Substituted Tungsten Molybdenum Oxide Based Zn 2+ Ion Intercalation Cathodes
|
journal | February 2019 |
A mechanistic study of mesoporous TiO 2 nanoparticle negative electrode materials with varying crystallinity for lithium ion batteries
|
journal | January 2020 |
Controlled hydroxy-fluorination reaction of anatase to promote Mg 2+ mobility in rechargeable magnesium batteries
|
journal | January 2018 |
Red-Shifted Absorptions of Cation-Defective and Surface-Functionalized Anatase with Enhanced Photoelectrochemical Properties
|
journal | June 2019 |
Similar Records
Layered Lepidocrocite Type Structure Isolated by Revisiting the Sol–Gel Chemistry of Anatase TiO 2 : A New Anode Material for Batteries
Identify OH groups in TiOF{sub 2} and their impact on the lithium intercalation properties