Enhancing the Thermoelectric Properties of Conjugated Polymers by Suppressing Dopant-Induced Disorder.

Doping is a crucial strategy to enhance the performance of various organic electronic devices. However, in many cases, the random distribution of dopants in conjugated polymers leads to the disruption of the polymer microstructure, severely constraining the achievable performance of electronic devices. Here, it is shown that by ion-exchange doping polythiophene-based P[(3HT)-stat-(T)] (x = 0 (P1), 0.

Electrical conductivity and glass formation in nitrile-functionalized pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquids: chain length and odd-even effects of the alkyl spacer between the pyrrolidinium ring and the nitrile group.

The electrical conductivity of a series of pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquids, functionalized with a nitrile (cyano) group at the end of an alkyl chain attached to the cation, was studied in the temperature range between 173 K and 393 K. The glass formation of the ionic liquids is influenced by the length of the alkyl spacer separating the nitrile function from the pyrrolidinium ring. The electrical conductivity and the viscosity do not show a monotonic dependence on the alkyl spacer length, but rather an odd-even effect.

Influence of the anion on the electrical conductivity and glass formation of 1-butyl-3-methylimidazolium ionic liquids.

Six ionic liquids based on the 1-butyl-3-methylimidazolium cation have been studied. As anions Cl(-), Br(-), I(-), [NCS](-), [N(CN)(2)](-), and [BF(4)](-) were selected. The electrical conductivities were determined between 173 and 393 K based on impedance measurements in the frequency range from 0.

Temperature dependence of the electrical conductivity of imidazolium ionic liquids.

The electrical conductivities of 1-alkyl-3-methylimidazolium tetrafluoroborate ionic liquids and of 1-hexyl-3-methylimidazolium ionic liquids with different anions were determined in the temperature range between 123 and 393 K on the basis of dielectric measurements in the frequency range from 1 to 10(7) Hz. Most of the ionic liquids form a glass and the conductivity values obey the Vogel-Fulcher-Tammann equation. The glass transition temperatures are increasing with increasing length of the alkyl chain.