A Soft-Solid Co-Crystalline Electrolyte Combining Advantages of Organics and Ceramics: Thermally, Electrochemically Stable, Highly Conductive (Adiponitrile)2LiPF6

Fall, Birane; Prakash, Prabhat; Aguirre, Jordan C.; Chereddy, Sumanth; Chinnam, Parameswara Rao; Dikin, Dmitriy A.; Venkatnathan, Arun; Wunder, Stephanie L.; Zdilla, Michael J.

doi:10.33774/chemrxiv-2021-n0d4x

Cited by 2 publications

(2 citation statements)

References 64 publications

(17 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the transition state, the Na + ion does not contact the ClO 4 – anion. In another work, a similar solvent-assisted migration of the Li + ion has also been observed, where the cyano group on adiponitrile supports the migration of Li + ions to an occupancy site at a distance of >0.6 nm, without any interference from anions …”

Section: Results and Discussionsupporting

confidence: 54%

“…We further examined the mechanism of this stimuli response from classical MD simulations with the effects of pressure and temperature. We also described that these crystals and others like them exhibit a nanoliquid surface layer resulting from the decreased lattice energy at the surface, which we have detected experimentally (SEM) and described using MD simulations on several materials. , This surface nanoliquid layer at the grain boundaries naturally binds grains to one another and facilitates ion conduction across electrolyte particles, circumventing the grain-boundary problem common to other solid electrolyte systems. Apart from these peculiar structural properties, these cocrystals exhibit a conductivity of 3 × 10 –4 S cm –1 with an E a barrier of 25 kJ mol –1 for Na + ion conduction calculated from temperature-dependent impedance spectroscopy measurements .…”

Section: Introductionmentioning

confidence: 71%

See 1 more Smart Citation

Mechanism of Ion Conduction and Dynamics in Tris(N,N-dimethylformamide) Perchloratosodium Solid Electrolytes

et al. 2022

Self Cite

View full text Add to dashboard Cite

(DMF)3NaClO4 is a soft-solid cocrystalline electrolyte with channels of Na+ ions, which can be reversibly converted to a less conductive form (DMF)2NaClO4 by the application of pressure or heat, leading to a melt- or press-castable electrolyte. Molecular dynamics simulations performed on the 3:1 stoichiometry suggest that Na+ ions conduct via a one-dimensional channel, which is supported by van-Hove autocorrelation function analysis. The simulations show that the transference number for Na+ ions is 0.43 at room temperature and exceeds 0.5 at higher temperatures in the molten mixture. The calculated activation energy for the diffusion of Na+ ions from MD simulations is 45 kJ mol–1. The minimum-energy path of Na+ ion migration in a 3:1 crystal is assessed using periodic density functional theory calculations, which provides a barrier of 33 kJ mol–1 for Na+ ion conduction, in reasonable agreement with the experimental value of 25 kJ mol–1. The motion of Na+ ions during conduction is vacancy-driven because the presence of a vacancy site enables jump events for Na+ ions. The activation energy is the penalty for a sodium ion to leave the octahedrally coordinated DMF ligand field via a transition state where only three molecules of DMF form a 3-O-Na trigonal planar geometry, with no involvement of ClO4 – in the coordination sphere of the transition state. In contrast, the calculated activation energy barrier for the 2:1 stoichiometry is higher (E a,DFT = 43 kJ mol–1, E a,exp = 49 kJ mol–1) due at least in part to the partial coordination of strongly binding perchlorate anions with Na+ ions in the transition state.

show abstract

Section: Results and Discussionsupporting

confidence: 54%