This data set accompanies the article "Tuning transport via interaction strength in cationic conjugated polyelectrolytes" published in Macromolecules in 2023 (10.1021/acs.macromol.3c01206). The article studies structure-property relationships for mixed lithium-electron conduction in organic polymers, emphasizing the importance of polymer-ion interaction strength.

This data set contains comprehensive characterization information- including ionic conductivity via electrochemical impedance spectroscopy (EIS), DC polarization, NMR Relaxometry, UV-Vis spectroscopy, electronic conductivity, and wide angle x-ray scattering. Data is presented in non-proprietary text, CSV, and TIF formats. Technique and sample identification is contained in the file titles, which correspond to figure numbers. Every column in each data file contains a header indicating the data that was recorded and the unit in which it was recorded. 

Ionic Conductivity

Ionic conductivity samples were prepared by first dissolving the appropriate amount of polymer in 50/50 methanol/acetonitrile for P3HT-Im⁺TFSI^– and P3HT-TMA⁺TFSI^–. It was found that 80/20 methanol/water was ideal for P3HT-NH₃⁺TFSI^–. LiTFSI/methanol solution was added to achieve the desired salt concentrations, and solutions were thoroughly mixed. The polymer/salt solution was then drop cast onto clean circular indium tin oxide (ITO) substrates top-coated with a 150 μm Kapton spacer in which a well of known diameter was punched. The samples were sealed with clean ITO substrates and dried under high vacuum (2 × 10^–8 torr) at 115°C for 12 hours. Samples were then loaded into an argon glovebox and loaded into a Controlled Environment Sample Holder (CESH) from Biologic LLC, which maintains an inert atmosphere during measurement. Variable temperature conductivity measurements were performed using Biologic’s Intermediate Temperature System (ITS) in conjunction with their VSP-300 potentiostat. A sinusoidal voltage with amplitude 100 mV was applied in the frequency range of 0.1 Hz-3 MHz. Data was then fit to the equivalent circuit shown in Figure S8 to extract the resistance.

NMR Relaxometry

Relaxometry measurements were performed on a 300 MHz Bruker Avance III super-wide-bore spectrometer with replaceable radio-frequency inserts for ⁷Li and ¹⁹F. A spin-locking frequency of 10 kHz was used in order to probe ion dynamics on a similar timescale (0.1 ms) as ionic conductivity measurements and to quantify the distribution of ions amongst the different local environments present in the polymer electrolytes of interest.

DC Polarization

Polymer/LiTFSI mixtures were placed in symmetric lithium−polymer−lithium cells in an argon glovebox utilizing a Controlled Environment Sample Holder (CESH) from Biologic LLC and tested using their Intermediate Temperature System (ITS) in conjunction with their VSP-300 potentiostat at a temperature of 80°C. After assembly, samples were allowed to rest overnight, then heated to 80°C and equilibrated until the interfacial resistance, monitored via EIS, stabilized. Next, a 100 mV potential bias was applied and the resulting current measured over time. Lithium transference numbers were calculated following the method of Bruce and Vincent.

Electronic Conductivity

Electronic conductivity was measured using custom-made gold digits on a thermal oxide silicon substrate.

UV-Vis Absorbance Spectroscopy

Samples were spun cast onto 0.5 mm thick quartz substrates in the same manner described for electronic conductivity. UV−Vis absorbance spectroscopy was performed on an Agilent Cary 60 UV−Vis Spectrophotometer.