Intercalation and Ordering of F₆TCNNQ and F₄TCNQ Dopants in Regioregular Poly(3-hexylthiophene) Crystals: Impact on Anisotropic Thermoelectric Properties of Oriented Thin Films

Redox doping is widely used to transform polymer semiconductors such as regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT) into conducting polymers. Strong acceptor molecules F6TCNNQ and F4TCNQ have been for sequential of aligned P3HT films produce with enhanced thermoelectric properties along the chain direction. This study uses polarized UV–vis–NIR spectroscopy electron diffraction clarify way dopant are introduced in crystals P3HT. A structural model obtained F6TCNNQ-doped (P-1 symmetry, a = 18.8 Å, b 8.95 c 7.75 α 107.6°, β 101.5°, γ 89.3°). The proposed structure consistent pattern results. predicts intercalation one per four thiophene monomers, reduction π-stacking distance, expansion unit cell alkyl side chains. Both TEM absorption demonstrate that better ordered than crystals, leading improved charge conductivities reaching 500 S/cm power factors close 80 μW m–1 K–2.