Disentangling cation effects on ion mobility and structure in ionic liquid electrolytes

Ionic liquids (ILs) are low-temperature molten salts, and therefore the transport of ions within ILs is dominated by ion-ion interactions. However, the influence of organic IL cations on key electrolyte properties, such as ion dissociation and overall transport behavior, in lithium-salt-doped ILs remains poorly understood. Moreover, despite their critical role in designing IL-based electrolytes for energy storage applications, ion-ion interactions and ion-specific transport under an applied electrical potential are seldom quantified, largely due to the unique experimental and computational challenges involved. Herein, we compare transport properties obtained using 1H, 7Li, and 19F pulsed-field gradient nuclear magnetic resonance (PFG NMR) and electrophoretic NMR (eNMR) with those measured by electrochemical impedance spectroscopy (EIS). Non-equilibrium molecular dynamics (MD) simulations and eNMR confirm the presence of negatively charged [Li(TFSI)n](1-n) aggregates that migrate towards..., PFG NMR:
All NMR measurements were performed on a Bruker Avance III 300 spectrometer with a 7.05 T super-wide bore (150 mm) superconducting magnet equipped with a Bruker Diff50 probe (maximum gradient strength of 28.98 T m–1), operating at 300.15 MHz for 1H, 116.65 MHz for 7Li, and 282.40 MHz for 19F. All measurements were performed at 313.15 K following at least 30 minutes of equilibration with the sample temperature controlled using dry N2 at a flow rate of 800 L h–1. 313.15 K was chosen as an application-relevant temperature that would allow for faster ionic mobility through a decreased viscosity and, therefore, more accurate measurements. Self-diffusion coefficients of the IL (C4C1im, C4C1pyrr, and C4C1pip) and Li+ cations, and TFSI– anion, were obtained from 1H, 7Li, and 19F PFG NMR experiments, respectively. Diffusivities were determined using a variable gradient strength stimulated echo pulse sequence designed to minimize signal loss from short transverse relaxation times (T2). T..., # Disentangling cation effects on ion mobility and structure in ionic liquid electrolytes

This README.md file was generated on 2026-01-22 by Leo W. Gordon.

**GENERAL INFORMATION**

Date of data collection: 2022-2024
Geographic location of data collection: Santa Barbara, CA, USA; Austin, TX, USA

**METHODOLOGICAL INFORMATION**

1. Description of methods used for collection/generation of data: See supporting information from published main text: [10.1088/2515-7655/ae3c3f](10.1088/2515-7655/ae3c3f).
2. Methods for processing the data: See supporting information from published text: [10.1088/2515-7655/ae3c3f](10.1088/2515-7655/ae3c3f).
3. Instrument- or software-specific information needed to interpret the
data: N/A
4. Standards and calibration information, if appropriate: N/A
5. Environmental/experimental conditions: See supporting information from published text: [10.1088/2515-7655/ae3c3f](10.1088/2515-7655/ae3c3f).
6. Describe any quality-assurance procedures performed on the data: ...,