You are kindly invited to attend the SCL online seminar of the Center for the Study of Complex Systems, which will be held on Thursday, 25 August 2022 at 14:00 on Zoom. The talk entitled

First-principles calculations of aluminum fluoride intercalation and diffusion in HOPG

will be given by Dr. Sindy Julieth Rodriguez Sotelo (Instituto de Fisica del Litoral - IFIS, Consejo Nacional de Investigaciones Cientificas y Tecnicas - CONICET Universidad Nacional del Litoral, Santa Fe, Argentina). Abstract of the talk:

Rechargeable batteries for electrical energy storage have attracted intense attention due to their lower environmental impact, portability, and high energy efficiency, and nowadays they are one of the most mature and widespread energy storage technologies [1,2]. Currently, the rechargeable batteries with the highest performance are lithium-ion-based (LIBs) due to their relatively high energy densities, good stability, and low self-discharge. However, the main shortcomings of LIBs are the limited lithium resources and the poor distribution of their raw materials worldwide [3]. Recently, interest in aluminum ion batteries has increased since, unlike LIBs, they have a low cost —–aluminum is in high abundance in the Earth’s crust—, are easy to handle in ambient conditions, and have a high theoretical capacity (with energy densities of 30-70 Wh/kg that results from the three-electron Al3(+)/Al redox couple)[4].

On the other hand, graphite is the material most commonly used as a cathode in ion batteries, mainly because of its ability to capture ions, atoms, or molecules inside it. Understanding the intercalation, diffusion, and adsorption processes of these ions/atoms/molecules on graphite is fundamental to the operation of the cathodes since the capacitance and operating voltage of the electrodes is determined by the structure and binding energy. In contrast, the rate of charge is determined by diffusion dynamics [5,6]. This seminar presents the results of a theoretical study of the intercalation and diffusion of aluminum fluoride (AlF3) in highly oriented pyrolytic graphite (HOPG). The talk is divided into three parts: (i) Superficial intercalation modeling for the neutral molecule AlF3 in HOPG, (ii) Bulk intercalation modeling for states 1 and 2, and (iii) molecular diffusion modeling in graphite and calculation of energy barriers. The reported results are contrasted with experiments and allow the evaluation of the use of AlF3 in rechargeable batteries.

References

[1] Gu X. Rechargeable metal batteries based on selenium cathode: progress, challenges and perspectives, J. Mater. Chem. A 2019, 7, 11566-11583.
[2] Goodenough J. et al. Challenges for Rechargeable Li Batteries. Chem. Mater., 2010, 22, 587–603.
[3] Armand M. et al. Building better batteries. Nature, 2008, 451, 652–657.
[4] Wang D.Y. et al. Advanced rechargeable aluminium ion battery with a high-quality natural graphite cathode. Nat Commun. 2017; 8: 14283.
[5] Candia A.E. et al. Aluminum fluoride intercalation in graphite for rechargeable batteries design. Carbon, 2022, 186, 724–736
[6] Rodriguez S.J. et al. A theoretical study on the intercalation and diffusion of AlF3 in graphite: its application in rechargeable batteries. Phys. Chem. Chem. Phys., 2021, 23, 19579.

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