The role of mobile organic radicals and ions (solitons, polarons and bipolarons) in the transport properties of doped conjugated polymers

Application of chemically synthesized conducting polymer-polypyrrole as a carbon dioxide gas sensor

“…Due to the -orbital overlap of neighboring molecules of the conjugated structure, the -electrons delocalize along the entire chain, which provide their semiconducting and conducting properties [29]. In doped PPy, a positive charge and an unpaired electron associated with a quoinoid structure are formed as a result of removal of an electron from a polymer chain [30], since CO 2 has two lone pair of electrons with -type C O bindings [31]. It may be possible that CO 2 molecules form weak bonds with -electrons of the PPy surface, which results in a decrease of conductivity or an increase in sensor resistance.…”

Electrical, thermal and spectroscopic studies of Te doped polyaniline

“…The most commonly accepted model [24][25][26][27] is that of polaron formation upon oxidation and combination of polarons gives bipolarons. The bipolarons are then free to move along the polymer chain, which gives rise to the electronic conductivity.…”

Voltammetric, EQCM, and in situ conductance studies of p- and n-dopable polymers based on ethylenedioxythiophene and bithiazole

“…Polythiazoles (PThz) exhibit a rare type of variable band gap behavior related to the degree of crystallinity in the solid state [21][22][23]. The incorporation of imine nitrogen into the conjugated backbone has led to the synthesis of n-dopable PThz's.…”