Poly(3,4‐ethylenedioxythiophene) in Dye‐Sensitized Solar Cells: Toward Solid‐State and Platinum‐Free Photovoltaics

Abstract

Dye-sensitized solar cells (DSSCs) have become a strong reality in the field of hybrid photovoltaics. Their ability to operate in diffused light conditions and the possibility of fabrication of modules bearing different colors make these cells attractive for different applications, for example, wearable electronics, building integration, etc. This review focuses on one of the compounds rather often studied for DSSCs, namely, poly(3,4-ethylenedioxythiophene) (PEDOT). It has been introduced both as a substitute for liquid electrolytes, in order to facilitate cells fabrication and increase their durability, and as an alternative to platinum for counter electrodes. The literature counts many studies on PEDOT and this manuscript collects them following a classification criterion based on applications, functionalization/doping strategies, and deposition methods. In addition to comparing the performance obtained for PEDOT-based systems with those of traditional cells (i.e., assembled with liquid iodine-based electrolytes and platinum cathodes), the manuscript also offers a brief analysis of costs and sustainability aspects, built up on experimental data found in the literature; this latter is expected to constitute a precious resource to catalyze the attention of the scientific community on relevant and preliminary aspects when figuring out the industrial scalability of newly proposed cell components.

Recent Progress on Self‐Healable Conducting Polymers

“…[99][100][101] Different dopants (e.g., PSS, tosylate, ClO 4 − , BF 4 − ) provide PEDOT with distinct electrical, mechanical, and electrochemical properties. [102][103][104][105][106] PEDOT-based conducting polymers show a tendency to adopt a lamellar stacking with alternating PEDOT and dopant layers. In PEDOT:PSS, due to the large size of the dopant anion and the resultant molecular stacking, the PEDOT chains adopt a coiled configuration with a benzoid structure.…”

Ladder-like Polymer Brushes Containing Conjugated Poly(Propylenedioxythiophene) Chains

“…Moreover, the 3,4-substitution also lowers the oxidation potential at which thiophene-based monomers undergo polymerization [ 22 ]. Among them, the most studied polymer is poly(3,4-ethylenedioxythiophene) (PEDOT) [ 23 , 24 ], which is one of the most chemically stable conjugated polymers, demonstrating high conductivity in the doped state (3000 S/cm or more, which is only slightly lower than the conductivity of metals) [ 25 , 26 ]. PEDOT intermixed and stabilized by poly(styrenesulfonate) (PSS) is probably the most popular and widely used polymer mixture in the field of conducting polymers—PEDOT:PSS [ 27 ].…”

Construction of a ternary system: a strategy for the rapid formation of porous poly(lactic acid) fibers

“…Fagiolari et al 2 outlined the application of poly(3,4-ethylenedioxythiophene) (PEDOT) as an ideal polymer organic conductor with excellent electrical conductivity, high flexibility, stability and low cost in the field of dye-sensitized solar cells (DSSCs). Beccatelli et al 3 demonstrated the functionalization of a commercial polyurethane (PU) foam with the conductive polymer PEDOT:PSS: the resulting material is a modified all-polymeric foam which can convert the material mechanical pressure into electrical signals.…”