Preparation and characterization of electropolymerized poly(3,4-ethylenedioxythiophene) thin films with different dopant anions

Abstract

We investigated the structural and thermoelectric properties poly(3,4-ethylenedioxythiophene) (PEDOT) films with several dopants (counter ions, ClO4, PF6, and BF4), synthesised by electropolymerization. We first performed cyclic voltammetry analysis to determine the optimum synthesis conditions of the PEDOT thin films. We found that the surface morphology of the PEDOT thin films was dependent on the type of the dopant. The PF6-doped PEDOT (PEDOT:PF6) thin films showed a dense structure, and the PEDOT:ClO4 thin films showed a highly porous microstructure. Fourier transform infrared (FT-IR) spectroscopy showed that all the PEDOT thin films showed similar chemical structures and the p-type state. Regarding their thermoelectric properties, the electrical conductivity of the all the doped PEDOT thin films increased as the dopant concentration increased, with the PEDOT:PF6 thin films showing the highest value. On the other hand, the Seebeck coefficient of the PEDOT thin films with all the dopants decreased as the dopant concentration increased, with the PEDOT:BF4 thin films achieving the highest value. As a result, the PEDOT:BF4 thin films exhibited the highest power factor of 0.75 µW/(m·K2) at a dopant concentration of 1.0 M. We think that the PEDOT microstructure produced using the different types of dopant may affect the thermoelectric properties.

Effects of different electrolytes and film thicknesses on structural and thermoelectric properties of electropolymerized poly(3,4-ethylenedioxythiophene) films

“…20 PEDOT thin lms can be synthesized both in organic and aqueous solutions using electrochemical methods. [21][22][23][24][25] Electropolymerization is known to be a reliable electrochemical method for fabrication of organic thin lms. 26,27 Electropolymerization of PEDOT thin lms in an organic solution has typically required the use of acetonitrile as the electrolyte solvent to polymerize the 3,4-ethylenedioxythiophene (EDOT) monomers.…”

Efficient and Stable Inverted Perovskite Solar Cell using Potassium Fluoroborate Doped PEDOT:PSS

“…The increase of J sc is due to the larger grain size of perovskite and enhanced light absorption. [ 18 ]…”

“…The increase of Jsc is due to the larger grain size of perovskite and enhanced light absorption. [18] We prepared 10 devices for each parameter under the same conditions. The statistical PCE, FF, Jsc, and Voc values of inverted PSCs with different KBF 4 concentrations are shown in Figure 6, and Table 1 summarizes the average photovoltaic performance of devices with different KBF 4 concentrations.…”

“…And BF4 − doped PEDOT:PSS can effectively enhance the PEDOT:PSS film conductivity. [ 18 ] Therefore, we came up with the idea of high electron affinity KBF 4 .…”

Effect of ultraviolet irradiation on poly(3,4-ethylenedioxythiophene) doped with ClO4thin films using electropolymerization

“…Recently, conducting polymers have attracted much attention because of their applicability in different devices such as thermoelectric devices, [1][2][3][4] solar cells, 5,6) field-effect transistors, 7,8) and electroluminescent devices. 9,10) Among conducting polymers, poly(3,4-ethylenedioxythiophene) (PEDOT) is the most promising material due to its electrochemically stable conjugated backbone structure; it exhibits high electrical conductivity when dopants such as poly(styrene sulfonate) (PSS), [11][12][13] tosylate (Tos), [14][15][16] and counter-ions (PF 6 , BF 4 , and ClO 4 ) [17][18][19] are incorporated. In addition, PEDOT exhibits a relatively low thermal conductivity even though the electrical conductivity is high.…”