Description du poste

Poly(3,4-ethylenedioxythiophene) (PEDOT) is one of the most widely studied intrinsically conducting polymers due to its unique properties with high electrical conductivity, optical transparency in the doped state, and environmental stability. [1] These properties have established PEDOT as a go-to material in diverse applications, including organic electronics, energy storage, photovoltaics, conductive inks, and electrocatalysis. A key factor in the commercialization of PEDOT has been its formulation as a composite complex with polystyrene sulfonate (PEDOT:PSS), where the polyanionic PSS serves simultaneously as the counterion and the dispersant, enabling the processing of stable aqueous dispersions into thin films. [2]
Despite these advantages, reliance on PSS presents some drawbacks. The strong acidity of PSS can be harmful to device stability and compatibility with other components. [3] Furthermore, PSS often impedes conductivity, requires post-treatments like secondary dopants or solvents to realign crystallite domains of PEDOT in the film and remove excess PSS. [4, 5]
As an alternative strategy, supported polymerization is being explored in recent years to tune morphology, conductivity and target specific applications. The support can guide the polymerization process and facilitate stabilization for intermediate products. [6]
This internship focuses on supported polymerization of PEDOT on various substrates: with different morphologies and surface chemistries and including their blends. We aim to understand how surface chemistry (OH density, surface charge and EDOT adsorption) and support geometry control nucleation, growth, and doping of PEDOT, and to maximize electrical conductivity. [7] We aim to incorporate these produced hybrid nanofillers into a thermoplastic matrix to obtain a conductive composite 3D printable material.

Objectives
1. Improve and establish a protocol for supported PEDOT polymerization
2. Correlate surface properties (accessible –OH groups, ζ-potential, anion density) with morphology and conductivity
3. Increase theoretical understanding of the mechanism of supported polymerization on clay surfaces

References
[1] L. Groenendaal, F. Jonas, D. Freitag, H. Pielartzik, J.R. Reynolds, Adv. Mater. 12 (2000) 481–494.
[2] S. Kirchmeyer, K. Reuter, J. Mater. Chem. 15 (2005) 2077–2088.
[3] P.J. Cameron, P.J. Skabara, Mater. Horiz. 7 (2020) 1759–1772.
[4] S. Hosseini, Z. Yu, et al., J. Mater. Chem. C 8 (2020) 3982–3990.
[5] N. Kim, S. Kee, S.H. Lee, B.H. Lee, Y.H. Kahng, Y.R. Jo, B.J. Kim, K. Lee, Nat. Commun. 5 (2014) 3583.
[6] M.N. Gueye, A. Carella, J. Faure-Vincent, R. Demadrille, J.P. Simonato,Prog. Mater. Sci. 108 (2020) 100616.
[7] J. Karst, et al., Polymer 290 (2024) 126577.

Descriptif du profil recherché

Candidate profile
1. MSc Year-2 in Chemistry / Physical Chemistry / Materials Science.
2. Experience in chemical lab and with classical characterization methods required
3. Experimental mindset, problem solving ability, scientific rigor, autonomy; English B2+.
4. Nice-to-have: experience with conducting polymers, colloids, surfaces, or any listed technique.

Conditions particulières d'exercice

Tasks
1. Prepare supports and additional surface treatments: mild HCl activation, support characterization
2. Quantify surface properties: BET (at ICPEES), ζ vs pH, –OH density and FTIR
3. Perform polymerizations under a fixed standard recipe (EDOT + FeCl₃, with SDS surfactant) so that the support is the primary variable
4. Characterize products: SEM/TEM, SAXS, FTIR / Raman (at ICUBE) / UV-Vis–NIR, DLS/ζ, and 4-point probe electrical measurements
5. Prepare a scientific report with publication style figures

Training outcomes
1. Study of inorganic supports; synthesis of conducting polymers by oxidative polymerization; mechanistic understanding and experimental design
2. Characterization (microscopy, spectroscopy, SAXS, electrical)
3. Data analysis, experimental design, and scientific writing
4. Possibility of co-authorship on publication depending on quality of results