Disordered rock salt
Disordered rock salts (DRX) are a class of materials bearing the rock salt crystal structure with a disordered arrangement of cations. They are most notable for their potential uses in lithium-ion battery cathodes.[1]
Structure
The atoms in disordered rock salts form a rock-salt structure,[1] in which the cations are arranged in a face-centered cubic (FCC) lattice with the anions occupying the octahedral holes.[2] The associated space group is Fm3m or 225, and the Strukturbericht designation is B1.[3]
Disordered rock salts are distinct from other rock salts in that there are multiple different cations present in the crystal structure. Cations and anions (typically oxygen anions) are still present in equal numbers, but each cation site may be occupied one of several cations. These cations are present in a fixed ratio, but they are randomly distributed with no long-range order.[4]
Use in lithium-ion batteries
Disordered rock salts are most notable for their potential uses in lithium-ion battery cathodes. Current lithium-ion battery cathodes, such as nickel-manganese-cobalt (NMC) or nickel-cobalt-aluminum (NCA) based cathodes, rely heavily on cobalt and nickel metals, which are scarce and expensive.[5][6] Cobalt is also toxic, and cobalt mining operations are often associated with human rights violations and environmental damage.[5]
Disordered rock salts offer a potential solution to many of these concerns. For example, manganese and titanium based disordered rock salts show promise as lithium-ion battery cathodes. These metals are both more abundant and less expensive than cobalt and nickel, addressing some of the issues with current cathodes.[1][5][6][7]
References
- ^ a b c Clément, R. J.; Lun, Z.; Ceder, G. (2020). "Cation-disordered rocksalt transition metal oxides and oxyfluorides for high energy lithium-ion cathodes". Energy & Environmental Science. 13 (2): 345–373. Bibcode:2020EnEnS..13..345C. doi:10.1039/C9EE02803J. Retrieved 20 August 2024.
- ^ "Rock salt structure". Oxford Reference. Oxford University Press. Retrieved 22 August 2024.
- ^ Mehl, Michael J.; Hicks, David; Toher, Cormac; Levy, Ohad; Hanson, Robert M.; Hart, Gus; Cultarolo, Stafano (2017). "The AFLOW Library of Crystallographic Prototypes: Part 1". Computational Materials Science. 136: S1–S828. doi:10.1016/j.commatsci.2017.01.017. Retrieved 22 August 2024.
- ^ Cambaz, Musa Ali; Urban, Alexander; Pervez, Syed Atif; Geßwein, Holger; Schiele, Alexander; Guda, Alexander; Bugaev, Aram; Mazilkin, Andrey; Diemant, Thomas; Behm, R. Jürgen; Brezesinski, Torsten; Fichtner, Maximilian (2020). "Understanding the Origin of Higher Capacity for Ni-Based Disordered Rock-Salt Cathodes". Chemistry of Materials. 32 (8): 3447–3461. doi:10.1021/acs.chemmater.9b05285. Retrieved 1 January 2025.
- ^ a b c Li, Tianyu; Geraci, Tullio; Koirala, Krishna Prasad; Zohar, Arava; Bassey, Euan; Chater, Philip; Wang, Chongmin; Navrotsky, Alexandra; Clément, Raphaële (2024). "Structural Evolution in Disordered Rock Salt Cathodes". Journal of the American Chemical Society. 146 (35): 24296–24309. Bibcode:2024JAChS.14624296L. doi:10.1021/jacs.4c04639. PMC 11378274. PMID 39172075.
- ^ a b Reuell, Peter (23 August 2024). "Study of disordered rock salts leads to battery breakthrough". MIT News. MIT News Office. Retrieved 4 January 2025.
- ^ Hau, Han-Ming; Holstun, Tucker; Lee, Eunryeol; Rinkel, Bernadine L. D.; Mishra, Tara P.; DiPrince, Max Markuson; Mohanakrishnan, Rohith Srinivaas; Self, Ethan C.; Persson, Kristin A.; McCloskey, Bryan D.; Ceder, Gerbrand (2025). "Disordered Rocksalts as High-Energy and Earth-Abundant Li-Ion Cathodes". Advanced Materials 2502766. doi:10.1002/adma.202502766. PMC 12631525. PMID 40326162. Retrieved 22 May 2025.