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Maria Magdalena Titirici - One of the best experts on this subject based on the ideXlab platform.
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Intercalation chemistry of graphite alkali metal ions and beyond
Chemical Society Reviews, 2019Co-Authors: Philipp Adelhelm, Maria Magdalena TitiriciAbstract:Reversibly intercalating ions into host materials for electrochemical energy storage is the essence of the working principle of rocking-chair type batteries. The most relevant example is the graphite anode for rechargeable Li-ion batteries which has been commercialized in 1991 and still represents the benchmark anode in Li-ion batteries 30 years later. Learning from past lessons on alkali metal Intercalation in graphite, recent breakthroughs in sodium and potassium Intercalation in graphite have been demonstrated for Na-ion batteries and K-ion batteries. Interestingly, some significant differences proved to exist for the Intercalation of Na+ and K+ into graphite compared with the Li+ case. Such different host-guest interactions are unique depending on the host materials and electrolytes, which greatly contribute to a deeper understanding of Intercalation-type electrode materials for next generation alkali metal ion batteries. This review summarizes significant advances from both experimental and theoretical calculations with a focus on comparing the Intercalation of three alkali metal ions (Li+, Na+, K+) into graphite and aims to clarify the intimate host-guest relationships and the underlying mechanisms. New approaches developed to achieve favorable Intercalation coupled with the challenges in this field are also discussed. We also extrapolate alkali metal ion Intercalation in graphite to mono-/multi-valent ions in layered electrode materials, which will deepen the understanding of Intercalation chemistry and provide guidance to explore new guests and hosts.
Takeshi Abe - One of the best experts on this subject based on the ideXlab platform.
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electrochemical lithium ion Intercalation into graphite electrode in propylene carbonate based electrolytes with dimethyl carbonate and calcium salt
Journal of Power Sources, 2013Co-Authors: Saya Takeuchi, Tomokazu Fukutsuka, Kohei Miyazaki, Takeshi AbeAbstract:Abstract Electrochemical Intercalation of Li+ ions into graphite electrodes in propylene carbonate (PC)-dimethyl carbonate (DMC)-based electrolytes containing Ca2+ ions was studied. The molar ratio of PC, Li+ ion, and Ca2+ ion was PC:Li+:Ca2+ = 12:1.0:0.5. Intercalation of Li+ ions became possible by adding DMC to the PC-based electrolytes containing Ca2+ ions: Li+ ion Intercalation did not take place when the amount of DMC was DMC/PC = 6 (molar ratio) and below, and Li+ ions intercalated when the amount of DMC was above DMC/PC = 8. Intercalation of Li+ ions did not take place in PC-DMC-based electrolyte of no Ca2+ ions, and both Ca2+ ion and DMC were necessary for Li+ ion Intercalation. Successful Li+ ion Intercalation can be attributed to smaller solvation number of PC on Li+ ions by addition of DMC and Ca2+ ions to the PC-based electrolyte.
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electrochemical preparation of a lithium graphite Intercalation compound in a dimethyl sulfoxide based electrolyte containing calcium ions
Carbon, 2013Co-Authors: Saya Takeuchi, Tomokazu Fukutsuka, Kohei Miyazaki, Takeshi AbeAbstract:Abstract Electrochemical preparation of lithium–graphite-Intercalation compound in dimethyl sulfoxide (DMSO)-based electrolytes containing calcium salt was studied. Intercalation of DMSO-solvated cation took place in 1.0 mol dm −3 lithium bis(trifluoromethanesulfonyl)amide (LiTFSA) + 1.5 mol dm −3 calcium bis(trifluoromethanesulfonyl)amide (Ca(TFSA) 2 )/DMSO, whereas Intercalation of Li + ions without solvent took place in 1.0 mol dm −3 LiTFSA + 2.5 mol dm −3 Ca(TFSA) 2 /DMSO. Raman spectroscopic study suggests absence of free DMSO in 1.0 mol dm −3 LiTFSA + 2.5 mol dm −3 Ca(TFSA) 2 /DMSO, which can lead to different solvation structure of Li + from the one in 1.0 mol dm −3 LiTFSA + 1.5 mol dm −3 Ca(TFSA) 2 /DMSO. Factors that are responsible for co-Intercalation and only Li + ion Intercalation are discussed based on the Li + ion solvation structures.
R Kotz - One of the best experts on this subject based on the ideXlab platform.
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a dilatometric study of lithium Intercalation into powder type graphite electrodes
Electrochemical and Solid State Letters, 2008Co-Authors: M Hahn, Hilmi Buqa, Patrick Ruch, Dietrich Goers, M E Spahr, Joachim Ufheil, Petr Novak, R KotzAbstract:The thickness change of porous multiparticle graphite electrodes upon first electrochemical lithium Intercalation and extraction was investigated by means of electrochemical dilatometry. For all investigated graphites, expansion starts well above 0.5 V vs Li/Li + and thus, before any unsolvated Li Intercalation compounds are formed. This finding can be explained by solvent co-Intercalation during the first charge prior to SEI formation, as described by the Besenhard model. At potentials <0.3 V vs Li/Li + , i.e., in the region of unsolvated Li + Intercalation, the dilatation curves reveal the same major staging features that are seen in the corresponding potential profiles.
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in situ x ray diffraction of the Intercalation of c2h5 4n and bf4 into graphite from acetonitrile and propylene carbonate based supercapacitor electrolytes
Electrochimica Acta, 2007Co-Authors: Patrick Ruch, M Hahn, Petr Novak, R Kotz, Fabio Rosciano, Michael Holzapfel, Hermann Kaiser, Werner Scheifele, B Schmitt, Alexander WokaunAbstract:Abstract The Intercalation of (C 2 H 5 ) 4 N + and BF 4 − from acetonitrile (AN) and propylene carbonate (PC) solutions into bound graphite electrodes during cyclic voltammetry was investigated by in situ X-ray diffraction (XRD) using synchrotron radiation. The disappearance of the 0 0 2 reflection of graphite in the XRD patterns upon Intercalation of (C 2 H 5 ) 4 N + indicates that the cations are accumulated between the graphene layers. For the Intercalation of BF 4 − , the appearance of 0 0 l reflexes in the intercalated state provides clear evidence of staging. In both cases, the in-plane periodicity was not significantly altered by the Intercalation process apart from slight changes in the C C bond length. The Intercalation of BF 4 − from the PC-based electrolyte was found to have the least destructive effect on the periodicity of the graphite structure during initial cycling in the anodic potential range along with the highest charge/discharge efficiency.
Judy J Cha - One of the best experts on this subject based on the ideXlab platform.
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Revisiting Intercalation‐Induced Phase Transitions in 2D Group VI Transition Metal Dichalcogenides
'Wiley', 2021Co-Authors: Mengjing Wang, Judy J ChaAbstract:Intercalation of alkali metals is widely studied to introduce a structural phase transition from 2H to 1T′ in 2D group VI transition metal dichalcogenides (TMDCs). This highly efficient phase transition method has enabled an access to a library of phases with novel physical and chemical properties attractive for functional devices and electrochemical catalysis. However, despite numerous studies that have predicted that charge doping mainly contributes to the structural phase transition in the Intercalation process, a mechanistic understanding of the phase transition at the atomic level has not been fully revealed. Furthermore, the coupled effects of strain and other intrinsic or extrinsic factors on the Intercalation‐induced phase transition have not been quantitatively determined. Herein, the progress of the Intercalation‐induced phase transition is briefly overviewed and the knowledge gaps in the current understanding of phase transition and Intercalation in 2D TMDCs are highlighted. To fully gain the microscopic picture of the Intercalation‐induced phase transition, in situ multimodal probes to monitor the real‐time structure−property relationship during Intercalation are suggested. The proposed research directions further direct material scientists to efficiently engineer phase transition pathways in 2D materials to explore novel functional phases
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Intercalation in two dimensional transition metal chalcogenides
Inorganic chemistry frontiers, 2016Co-Authors: Yeonwoong Jung, Yu Zhou, Judy J ChaAbstract:Intercalation is a reversible insertion process of foreign species into crystal gaps. Layered materials are good host materials for various intercalant species ranging from small ions to atoms to molecules. Given the recent intense interest in two-dimensional (2D) layered materials in thin limits, this review highlights the opportunities that Intercalation chemistry can provide for nanoscale layered materials. Novel heterostructures or emergent electrical properties not found in the intrinsic host materials are possible with Intercalation. In particular, we review various exfoliation methods developed for 2D layered nanomaterials based on Intercalation chemistry and extensive tuning of the electrical, optical, and magnetic properties of 2D layered materials due to Intercalation.
Patrick Ruch - One of the best experts on this subject based on the ideXlab platform.
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a dilatometric study of lithium Intercalation into powder type graphite electrodes
Electrochemical and Solid State Letters, 2008Co-Authors: M Hahn, Hilmi Buqa, Patrick Ruch, Dietrich Goers, M E Spahr, Joachim Ufheil, Petr Novak, R KotzAbstract:The thickness change of porous multiparticle graphite electrodes upon first electrochemical lithium Intercalation and extraction was investigated by means of electrochemical dilatometry. For all investigated graphites, expansion starts well above 0.5 V vs Li/Li + and thus, before any unsolvated Li Intercalation compounds are formed. This finding can be explained by solvent co-Intercalation during the first charge prior to SEI formation, as described by the Besenhard model. At potentials <0.3 V vs Li/Li + , i.e., in the region of unsolvated Li + Intercalation, the dilatation curves reveal the same major staging features that are seen in the corresponding potential profiles.
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in situ x ray diffraction of the Intercalation of c2h5 4n and bf4 into graphite from acetonitrile and propylene carbonate based supercapacitor electrolytes
Electrochimica Acta, 2007Co-Authors: Patrick Ruch, M Hahn, Petr Novak, R Kotz, Fabio Rosciano, Michael Holzapfel, Hermann Kaiser, Werner Scheifele, B Schmitt, Alexander WokaunAbstract:Abstract The Intercalation of (C 2 H 5 ) 4 N + and BF 4 − from acetonitrile (AN) and propylene carbonate (PC) solutions into bound graphite electrodes during cyclic voltammetry was investigated by in situ X-ray diffraction (XRD) using synchrotron radiation. The disappearance of the 0 0 2 reflection of graphite in the XRD patterns upon Intercalation of (C 2 H 5 ) 4 N + indicates that the cations are accumulated between the graphene layers. For the Intercalation of BF 4 − , the appearance of 0 0 l reflexes in the intercalated state provides clear evidence of staging. In both cases, the in-plane periodicity was not significantly altered by the Intercalation process apart from slight changes in the C C bond length. The Intercalation of BF 4 − from the PC-based electrolyte was found to have the least destructive effect on the periodicity of the graphite structure during initial cycling in the anodic potential range along with the highest charge/discharge efficiency.