Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 2208.14420

The Intercalation Chemistry of the Disordered RockSalt Li3V2O5 Anode from Cluster Expansions and Machine Learning Interatomic Potentials

Xingyu Guo·Chi Chen·Shyue Ping Ong
View original source ↗Read source document ↗Export metadata ↓

Abstract

Disordered rocksalt (DRX) Li3V2O5 is a promising candidate for anode in rechargeable lithium-ion batteries because of its ideal low voltage, high rate capability, and superior cycling stability. Herein, we presents a comprehensive study of intercalation chemistry of the DRX-Li3V2O5 anode using density functional theory calculations combined with machine learning cluster expansions and interatomic potentials. The predicted voltage profile of the disordered Li3V2O5 anode at room temperature based on Monte Carlo simulations with a fitted cluster expansion model is in excellent agreement with experiments. In contrast to previous DFT results, we find that Li ions predominately intercalate into tetrahedral sites during charging, while the majority of Li and V ions at octahedral sites remain stable. In addition, MD simulations with a fitted moment tensor potential attribute the fast-charging capability of DRX-Li3V2O5 to the facile diffusivity of Li+ via tetrahedral - octahedral - tetrahedral pathway. We further suggest tuning the Li:V ratio as a means to trade off increased lithiation capacity and decreased anode voltage in this system. This work provides in-depth insights into the high-performance DRX-Li3V2O5 anode, and paves the way to the discovery of other disordered anode materials.

Explore related subjects

cond-mat.mtrl-sci

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Xingyu Guo, Chi Chen, Shyue Ping Ong. 2022-08-30. The Intercalation Chemistry of the Disordered RockSalt Li3V2O5 Anode from Cluster Expansions and Machine Learning Interatomic Potentials. https://arxiv.org/abs/2208.14420

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Incommensurate structural and magnetic modulations in potassium-rich cryptomelane, K$_x$Mn$_8$O$_{16}$ ($x\approx1.45$)

Cryptomelane is a hollandite-like material consisting of K$^+$ cations in an $α$-MnO$_2$ tunnel-like crystallographic motif. Cryptomelane with stoichiometry K$_x$Mn$_8$O$_{16}$ ($x\approx1.45$) has been synthesized and its magnetic properties investigated using variable-temperature magnetic susceptibility, heat capacity, and neutron powder diffraction. Three distinct transitions at $T_1=184$\,K, $T_2=54.5$\,K, and $T_3=24$\,K are observed. At $T_1$ there is a subtle tetragonal$\rightarrow$monoclinic transition associated with emergence of a set of non-magnetic superstructure peaks indexable to a $\vec{k}_\mathrm{struc}\approx0.74\vec{c^*}$ incommensurate modulation parallel to the $α$-MnO$_2$ tunnels. Our findings are consistent with a relation previously reported in titanate hollandites, that $x\approx2|\vec{k}_\mathrm{struc}|$. Magnetic Bragg peaks emerge below $T_2=54.5$\,K, and their positions indicate an incommensurate modulated magnetic structure. The model consistent with the data is a dual-$\vec{k}_\mathrm{mag}$ structure with a ferromagnetic $|\vec{k}_\mathrm{mag}|=0$ component and an incommensurate $\vec{k}_\mathrm{mag}\approx0.37\vec{c^*}$, with the latter most likely to be helical. The period of oscillation of the incommensurate magnetic component is in line with predictions based on a Heisenberg spin Hamiltonian [Mandal \textit{et al}. Phys. Rev. B 90, 104420 (2014)]. Below $T_3=24$\,K, there is a magnetic transition, which gives rise to a different set of magnetic Bragg peaks indicative of a highly complex magnetic structure.

cond-mat.mtrl-sci↗
arXiv2026

An anisotropic functional for two-dimensional material systems

Density function theory is the workhorse of modern electronic structure theory. However, its accuracy in practical calculations is limited by the choice of the exchange-correlation potential. In this respect, two-dimensional materials pose a special challenge, as all these materials and their heterostructures have a crucial similarity. The underlying atomic structures are strongly spatially inhomogeneous, implying that current exchange-correlation functionals, that in almost all cases are isotropic, are ill-prepared for an accurate description. We present an anisotropic screened-exchange potential, that remedies this problem and reproduces the band-gap of 2D materials as well as the piecewise linearity of the total energy with fractional occupation number.

cond-mat.mtrl-sci↗
arXiv2026

Thermally-driven reorientation of the Néel vector in altermagnetic MnTe

Altermagnets are novel magnetic systems that possess a spin-polarized electronic band structure without a net magnetic moment, making them promising for device applications. Hexagonal MnTe, a prototypical altermagnet, arguably exhibits the most properties consistent with theoretical predictions, including an anomalous Hall effect despite a vanishing net magnetization, and altermagnetinduced electronic band splitting. However, fundamental questions remain, including why some effects only appear significantly below the magnetic ordering temperature. Here, we resolve this discrepancy by revealing a reorientation of the Néel vector in single-crystalline MnTe. The Néel vector points 30° from the a-axis at low $T$, before aligning directly with the a-axis around $T\simeq 260$ K. We attribute this to single-ion anisotropy, which depends on temperature-dependent lattice parameters. We obtained these results using muon-spin spectroscopy, magnetization measurements, and X-ray diffraction; we show that the findings are consistent with neutron diffraction. Manipulating this effect, for example through strain, could unlock sensitive electronic detection schemes for external stimuli, paving the way for functional altermagnetic devices.

cond-mat.mtrl-sci↗