2024 New's Items

Gold–Thiolate Nanocluster Dynamics and Intercluster Reactions Enabled by a Machine Learned Interatomic Potential

McCandler, C. A.
Pihlajamäki, A.
Malola, S.
Häkkinen, H.
Persson, K. A.
2024

Monolayer protected metal clusters comprise a rich class of molecular systems and are promising candidate materials for a variety of applications. While a growing number of protected nanoclusters have been synthesized and characterized in crystalline forms, their dynamical behavior in solution, including prenucleation cluster formation, is not well understood due to limitations both in characterization and first-principles modeling techniques. Recent advancements in machine-learned interatomic potentials are rapidly enabling the study of complex interactions such as dynamical behavior and...

Solubilities of Ethylene and Carbon Dioxide Gases in Lithium-Ion Battery Electrolyte

Soto, M.
Fink, K.
Zweifel, C.
Weddle, P. J.
Spotte-Smith, E. W. C.
Veith, G. M.
Persson, K. A.
Colclasure, A. M.
Tremolet de Villers, B. J.
2024

During Li-ion battery operation, (electro)chemical side reactions occur within the cell that can promote or degrade performance. These complex reactions produce byproducts in the solid, liquid, and gas phases. Studying byproducts in these three phases can help optimize battery lifetimes. To relate the measured gas-phase byproducts to species dissolved in the liquid-phase, equilibrium proprieties such as the Henry’s law constants are required. The present work implements a pressure decay experiment to determine the thermodynamic equilibrium concentrations between the gas and liquid phases...

The Role of Alkalis in Orchestrating Uranyl-Peroxide Reactivity Leading to Direct Air Capture of Carbon Dioxide

Arteaga, A.
Arino, T.
Moore, G. C.
Bustos, J. L.
Horton, M. K.
Persson, K. A.
Li, J.
Stickle, W. F.
Kohlgruber, T. A.
Surbella, R. G. III
Nyman, M.
2024

Spectator ions have known and emerging roles in aqueous metal-cation chemistry, respectively directing solubility, speciation, and reactivity. Here, we isolate and structurally characterize the last two metastable members of the alkali uranyl triperoxide series, the Rb+ and Cs+ salts (Cs-U1 and Rb-U1). We document their rapid solution polymerization via small-angle X-ray scattering, which is compared to the more stable Li+, Na+ and K+ analogues. To understand the role of the...

Overcoming systematic softening in universal machine learning interatomic potentials by fine-tuning

Deng, B.
Choi, Y.
Zhong, P.
Riebesell, J.
Anand, S.
Li, Z.
Jun, K.
Persson, K. A.
Ceder, G.
2024

Machine learning interatomic potentials (MLIPs) have introduced a new paradigm for atomic simulations. Recent advancements have seen the emergence of universal MLIPs (uMLIPs) that are pre-trained on diverse materials datasets, providing opportunities for both ready-to-use universal force fields and robust foundations for downstream machine learning refinements. However, their performance in extrapolating to out-of-distribution complex atomic environments remains unclear. In this study, we highlight a consistent potential energy surface (PES) softening effect in three uMLIPs: M3GNet, CHGNet...

Design Principles and Routes for Calcium Alkoxyaluminate Electrolytes

Leon, N. J.
Ilic, S.
Xie, X.
Jeong, H.
Yang, Z.
Wang, B.
Spotte-Smith, E. W. C.
Stern, C.
Hahn, N.
Zavadil, K.
Cheng, L.
Persson, K. A.
Connell, J. G.
Liao, C.
2024

Multivalent-ion battery technologies are increasingly attractive options for meeting diverse energy storage needs. Calcium ion batteries (CIB) are particularly appealing candidates for their earthly abundance, high theoretical volumetric energy density, and relative safety advantages. At present, only a few Ca-ion electrolyte systems are reported to reversibly plate at room temperature: for example, aluminates and borates, including Ca[TPFA]2, where [TPFA]− = [Al(OC(CF3)3)4]− and Ca[B(hfip)4]2...

First-Principles and Experimental Investigation of ABO4 Zircons as Calcium Intercalation Cathodes

Kim, J.
Sari, D.
Chen, Q.
Rutt, A.
Ceder, G.
Persson, K. A.
2024

Identifying next-generation batteries with multivalent ions, such as Ca2+ is an active area of research to meet the increasing demand for large-scale, renewable energy storage solutions. Despite the promise of higher energy densities with multivalent batteries, one of their main challenges is addressing the sluggish kinetics in cathodes that arise from stronger electrostatic interactions between the multivalent ion and host lattice. In this paper, zircons are theoretically and experimentally evaluated as Ca cathodes. A migration barrier as low as 113 meV is...

Switching the spin cycloid in BiFeO3 with an electric field

Meisenheimer, P.
Moore, G.
Zhou, S.
Zhang, H.
Huang, X.
Husain, S.
Chen, X.
Martin, L. W.
Persson, K. A.
Griffin, S.
Caretta, L.
Stevenson, P.
Ramesh, R.
2024

Bismuth ferrite (BiFeO3) is a multiferroic material that exhibits both ferroelectricity and canted antiferromagnetism at room temperature, making it a unique candidate in the development of electric-field controllable magnetic devices. The magnetic moments in BiFeO3 are arranged into a spin cycloid, resulting in unique magnetic properties which are tied to the ferroelectric order. Previous understanding of this coupling has relied on average, mesoscale measurements. Using nitrogen vacancy-based diamond magnetometry, we observe the magnetic spin cycloid structure of...

Deconvolution and Analysis of the 1H NMR Spectra of Crude Reaction Mixtures

Venetos, M. C.
Elkin, M.
Delaney, C.
Hartwig, J. F.
Persson, K. A.
2024

Nuclear magnetic resonance (NMR) spectroscopy is an important analytical technique in synthetic organic chemistry, but its integration into high-throughput experimentation workflows has been limited by the necessity of manually analyzing the NMR spectra of new chemical entities. Current efforts to automate the analysis of NMR spectra rely on comparisons to databases of reported spectra for known compounds and, therefore, are incompatible with the exploration of new chemical space. By reframing the NMR spectrum of a reaction mixture as a joint probability distribution, we have used...

Oxygen Transport through Amorphous Cathode Coatings in Solid-State Batteries

Cheng, J.
Peng, X.
Zhang, Y.-Q.
Tian, Y.
Ogunfunmi, T.
Haddad, A. Z.
Dopilka, A.
Ceder, G.
Persson, K. A.
Scott, M. C.
2024
All solid-state batteries (SSBs) are considered the most promising path to enabling higher energy-density portable energy, while concurrently improving safety as compared to current liquid electrolyte solutions. However, the desire for high energy necessitates the choice of high-voltage cathodes, such as nickel-rich layered oxides, where degradation phenomena related to oxygen loss and structural densification at the cathode surface are known to significantly compromise the cycle and thermal stability. In this work, we show, for the first time, that even in an SSB, and when protected by...

Complete miscibility of immiscible elements at the nanometre scale

Chen, P.-C.
Gao, M.
McCandler, C. A.
Song, C.
Jin, J.
Yang, Y.
Maulana, A. L.
Persson, K. A.
Yang, P.
2024

Understanding the mixing behaviour of elements in a multielement material is important to control its structure and property. When the size of a multielement material is decreased to the nanoscale, the miscibility of elements in the nanomaterial often changes from its bulk counterpart. However, there is a lack of comprehensive and quantitative experimental insight into this process. Here we explored how the miscibility of Au and Rh evolves in nanoparticles of sizes varying from 4 to 1 nm and composition changing from 15% Au to 85% Au. We found that the two immiscible elements exhibit a...