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Lithium-ion batteries (LIBs) are ubiquitous in everyday applications. However, Lithium (Li) is a limited resource on the planet and, therefore, not sustainable. As an alternative to lithium, earth-abundant and cheaper multivalent metals such as aluminum (Al) and calcium (Ca) have been actively researched in battery systems. However, finding suitable intercalation hosts for multivalent-ion batteries is urgently needed. Open-tunneled oxides represent a specific category of microparticles distinguished by the presence of integrated one-dimensional channels or nanopores. This work focuses on two promising open-tunnel oxides: Niobium Tungsten Oxide (NTO) and Molybdenum Vanadium Oxide (MoVO). The MoVO structure can accommodate a larger number of multivalent ions than NTO due to its larger surface area and different shapes. Specifically, the MoVO structure can adsorb Ca, Li, and Al ions with adsorption potentials ranging from around 4 to 5 eV. However, the adsorption potential for hexagonal channels of Al ion drops to 1.73 eV due to the limited channel area. The NTO structure exhibits an insertion/adsorption potential of 4.4 eV, 3.4 eV, and 0.9 eV for one Li, Ca, and Al, respectively. Generally, Ca ions are more readily adsorbed than Al ions in both MoVO and NTO structures. Bader charge analysis and charge density plots reveal the role of charge transfer and ion size in the insertion of multivalent ions such as Ca and Al into MoVO and NTO systems. Exploring open-tunnel oxide materials for battery applications is hindered by vast compositional possibilities. The execution of experimental trials and quantum-based simulations is not viable for addressing the challenge of locating a specific item within a large and complex set of possibilities. Therefore, it is imperative to conduct structural stability testing to identify viable combinations with sufficient pore topologies. Data mining and machine learning techniques are employed to discover innovative transitional metal oxide materials. This study compares two machine learning algorithms, one utilizing descriptors and the other employing graphs to predict the synthesizability of new materials inside a laboratory setting. The outcomes of this study offer valuable insights into the exploration of alternative naturally occurring multiscale particles.
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This content will become publicly available on April 29, 2026
Adsorption mechanism of carbonate ion on the (111) surface of tricalcium silicate through DFT simulations
This study investigates the adsorption mechanism of CO3^(2−) on the (111) surface of tricalcium silicate (C3S) using density functional theory simulations. Two distinct adsorption configurations were identified: a tilted alignment with localised bonding to Ca ions and concentrated charge transfer, and a parallel orientation with delocalised interactions involving multiple Ca ions. Charge density analysis revealed charge transfer from the surface to the carbonate molecule, with electron accumulation around oxygen atoms of CO3^(2−). Partial density of states analysis showed significant changes near the Fermi level after adsorption, indicating the formation of new bonding states. Molecular dynamics simulations demonstrated that the tilted configuration stabilises the surface by reducing Ca ion mobility, while the parallel configuration leads to increased ion mobility and higher surface reactivity. These findings emphasise the importance of site-specific interactions and electronic structure changes in understanding CO2 mineralisation mechanisms in cementitious materials.
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- Award ID(s):
- 1944921
- PAR ID:
- 10612164
- Publisher / Repository:
- Taylor and Francis
- Date Published:
- Journal Name:
- Molecular Physics
- ISSN:
- 0026-8976
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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