journal article·2025-07-26Open access

Robust and flexible organic electrochemical transistors enabled by electropolymerized PEDOT

Meijing Wang, Jiaxin Fan, Michel Bilodeau-Calame, Chihyeong Kim, Cheng-Ling Chiang, Ademar Fabricio Chaverri Segura, Vito Vurro, Ilaria Bargigia, Janine Mauzeroll, Fabio Cicoira

npj Flexible Electronics· Volume 9· Issue 1

Abstract

Organic electrochemical transistors (OECTs) based on poly(3,4-ethylenedioxythiophene) (PEDOT) have been extensively studied, yet devices fabricated via electropolymerization remain underexplored in terms of the underlying ionic dynamics and the potential for flexible integration. In this work, we demonstrate robust OECTs based on electropolymerized PEDOT, exhibiting negligible drain current degradation after 1000 cycles of operation in aqueous NaCl. Compared to inkjet-printed devices, they offer markedly superior cycling stability, which is further enhanced by the incorporation of the small anionic dopant ClO 4 − . We also show flexible, lightweight OECTs by electropolymerizing PEDOT on ultrathin parylene substrates, achieving stable performance under mechanical strain. Furthermore, Electrochemical Quartz Crystal Microbalance with Dissipation (EQCM-D) analysis reveals distinct ion transport behavior in PEDOT:ClO 4 , where dopant ejection dominates doping/dedoping process, unlike in PEDOT:PSS. This study underscores the advantages of electropolymerization and small-ion doping, offering new mechanistic insights and advancing the design of high-performance, flexible OECTs for bioelectronic applications.
Source: openalex_inverted_index · Quality: baseline

Research context

OpenAlex topics: Conducting polymers and applications · Advanced Sensor and Energy Harvesting Materials · Analytical Chemistry and Sensors

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (63)

Show source-provided references
1. Rivnay, J. et al. Organic electrochemical transistors. Nat. Rev. Mater. 3, https://doi.org/10.1038/natrevmats.2017.86 (2018).10.1038/natrevmats.2017.86 ↗
2. Nawaz, A., Liu, Q., Leong, W. L., Fairfull-Smith, K. E. & Sonar, P. Organic electrochemical transistors for in vivo bioelectronics. Adv. Mater. 33, e2101874 (2021).10.1002/adma.202101874 ↗
3. Leleux, P. et al. Organic electrochemical transistors for clinical applications. Adv. Healthc. Mater. 4, 142–147 (2015).10.1002/adhm.201400356 ↗
4. Marks, A., Griggs, S., Gasparini, N. & Moser, M. Organic electrochemical transistors: an emerging technology for biosensing. Adv. Mater. Interfaces 9, https://doi.org/10.1002/admi.202102039 (2022).10.1002/admi.202102039 ↗
5. Harikesh, P. C. et al. Organic electrochemical neurons and synapses with ion mediated spiking. Nat. Commun. 13, 901 (2022).10.1038/s41467-022-28483-6 ↗
6. van de Burgt, Y. et al. A non-volatile organic electrochemical device as a low-voltage artificial synapse for neuromorphic computing. Nat. Mater. 16, 414–418 (2017).10.1038/nmat4856 ↗
7. Azimi, M., Subramanian, A., Fan, J., Soavi, F. & Cicoira, F. Electrical and mechanical stability of flexible, organic electrolyte-gated transistors based on iongel and hydrogels. J. Mater. Chem. C. 11, 4623–4633 (2023).10.1039/D3TC00410D ↗
8. Paulsen, B. D., Tybrandt, K., Stavrinidou, E. & Rivnay, J. Organic mixed ionic-electronic conductors. Nat. Mater. 19, 13–26 (2020).10.1038/s41563-019-0435-z ↗
9. Torricelli, F. et al. Electrolyte-gated transistors for enhanced performance bioelectronics. Nat. Rev. Methods Primers 1, https://doi.org/10.1038/s43586-021-00065-8 (2021).10.1038/s43586-021-00065-8 ↗
10. Khodagholy, D. et al. High transconductance organic electrochemical transistors. Nat. Commun. 4, 2133 (2013).10.1038/ncomms3133 ↗
11. Rivnay, J. et al. Organic electrochemical transistors with maximum transconductance at zero gate bias. Adv. Mater. 25, 7010–7014 (2013).10.1002/adma.201303080 ↗
12. Zhang, S. et al. Solvent-induced changes in PEDOT:PSS films for organic electrochemical transistors. APL Mater. 3, https://doi.org/10.1063/1.4905154 (2015).10.1063/1.4905154 ↗
13. Kim, S. M. et al. Influence of PEDOT:PSS crystallinity and composition on electrochemical transistor performance and long-term stability. Nat. Commun. 9, 3858 (2018).10.1038/s41467-018-06084-6 ↗
14. Rivnay, J. et al. Structural control of mixed ionic and electronic transport in conducting polymers. Nat. Commun. 7, 11287 (2016).10.1038/ncomms11287 ↗
15. Romele, P., Ghittorelli, M., Kovacs-Vajna, Z. M. & Torricelli, F. Ion buffering and interface charge enable high performance electronics with organic electrochemical transistors. Nat. Commun. 10, 3044 (2019).10.1038/s41467-019-11073-4 ↗
16. Wang, S. et al. An organic electrochemical transistor for multi-modal sensing, memory and processing. Nat. Electron. 6, 281–291 (2023).10.1038/s41928-023-00950-y ↗
17. Zabihipour, M. et al. High yield manufacturing of fully screen-printed organic electrochemical transistors. npj Flex. Electron. 4, https://doi.org/10.1038/s41528-020-0078-9 (2020).10.1038/s41528-020-0078-9 ↗
18. Kim, C. H. et al. All-printed and stretchable organic electrochemical transistors using a hydrogel electrolyte. Nanoscale 15, 3263–3272 (2023).10.1039/D2NR06731E ↗
19. Fan, J., Montemagno, C. & Gupta, M. 3D printed high transconductance organic electrochemical transistors on flexible substrates. Org. Electron. 73, 122–129 (2019).10.1016/j.orgel.2019.06.012 ↗
20. Basiricò, L. et al. Electrical characteristics of ink-jet printed, all-polymer electrochemical transistors. Org. Electron. 13, 244–248 (2012).10.1016/j.orgel.2011.11.010 ↗
21. Fan, J., Forero Pico, A. A. & Gupta, M. A functionalization study of aerosol jet printed organic electrochemical transistors (OECTs) for glucose detection. Mater. Adv. 2, 7445–7455 (2021).10.1039/D1MA00479D ↗
22. White, H. S., Kittlesen, G. P. & Wrighton, M. S. Chemical derivatization of an array of three gold microelectrodes with polypyrrole: fabrication of a molecule-based transistor. J. Am. Chem. Soc. 106, 5375–5377 (1984).10.1021/ja00330a070 ↗
23. Paul, E. W., Ricco, A. J. & Wrighton, M. S. Resistance of polyaniline films as a function of electrochemical potential and the fabrication of polyaniline-based microelectronic devices. J. Phys. Chem. 89, 1441–1447 (1985).10.1021/j100254a028 ↗
24. Thackeray, J. W., White, H. S. & Wrighton, M. S. Poly (3-methylthiophene)-coated electrodes: optical and electrical properties as a function of redox potential and amplification of electrical and chemical signals using poly (3-methylthiophene)-based microelectrochemical transistors. J. Phys. Chem. 89, 5133–5140 (1985).10.1021/j100269a048 ↗
25. Thackeray, J. W. & Wrighton, M. S. Chemically responsive microelectrochemical devices based on platinized poly (3-methylthiophene): variation in conductivity with variation in hydrogen, oxygen, or pH in aqueous solution. J. Phys. Chem. 90, 6674–6679 (1986).10.1021/j100283a016 ↗
26. Gerasimov, J. Y. et al. A biomimetic evolvable organic electrochemical transistor. Adv. Electron. Mater. 7, https://doi.org/10.1002/aelm.202001126 (2021).10.1002/aelm.202001126 ↗
27. Gerasimov, J. Y. et al. An evolvable organic electrochemical transistor for neuromorphic applications. Adv. Sci. 6, 1801339 (2019).10.1002/advs.201801339 ↗
28. Janzakova, K. et al. Dendritic organic electrochemical transistors grown by electropolymerization for 3d neuromorphic engineering. Adv. Sci. 8, e2102973 (2021).10.1002/advs.202102973 ↗
29. Cucchi, M. et al. Directed growth of dendritic polymer networks for organic electrochemical transistors and artificial synapses. Adv. Electron. Mater. 7 https://doi.org/10.1002/aelm.202100586 (2021).10.1002/aelm.202100586 ↗
30. Wustoni, S. et al. In situ electrochemical synthesis of a conducting polymer composite for multimetabolite sensing. Adv. Mater. Technol. 5, https://doi.org/10.1002/admt.201900943 (2019).10.1002/admt.201900943 ↗
31. Fenoy, G. E. et al. “Clickable” organic electrochemical transistors. J. Am. Chem. Soc. 2, 2778–2790 (2022).
32. Fenoy, G. E. et al. Interface engineering of “clickable” organic electrochemical transistors toward biosensing devices. ACS Appl. Mater. Interfaces 15, 10885–10896 (2023).10.1021/acsami.2c21493 ↗
33. Fenoy, G. E. et al. A poly(3,4-ethylenedioxythiophene) derivative incorporating ethynyl moieties for click chemistry-based bioelectronics. Chem. Mater. 36, 7207–7221 (2024).10.1021/acs.chemmater.4c00989 ↗
34. Brodsky, J. et al. Downsizing the channel length of vertical organic electrochemical transistors. ACS Appl. Mater. Interfaces 15, 27002–27009 (2023).10.1021/acsami.3c02049 ↗
35. Hagler, J. E. et al. Electrodeposited PEDOT:BF4 coatings improve impedance of chronic neural stimulating probes in vivo. Adv. Mater. Interfaces 9, https://doi.org/10.1002/admi.202201066 (2022).10.1002/admi.202201066 ↗
36. Bodart, C. et al. Electropolymerized poly(3,4-ethylenedioxythiophene) (PEDOT) coatings for implantable deep-brain-stimulating microelectrodes. ACS Appl. Mater. Interfaces 11, 17226–17233 (2019).10.1021/acsami.9b03088 ↗
37. Lee, J. et al. Electrochemical fabrication and characterization of organic electrochemical transistors using poly(3,4-ethylenedioxythiophene) with various counterions. ACS Appl. Mater. Interfaces 14, 42289–42297 (2022).10.1021/acsami.2c10149 ↗
38. Flagg, L. Q. et al. Polymer crystallinity controls water uptake in glycol side-chain polymer organic electrochemical transistors. J. Am. Chem. Soc. 141, 4345–4354 (2019).10.1021/jacs.8b12640 ↗
39. Wu, R., Paulsen, B. D., Ma, Q. & Rivnay, J. Mass and charge transport kinetics in an organic mixed ionic–electronic conductor. Chem. Mater. 34, 9699–9710 (2022).10.1021/acs.chemmater.2c02476 ↗
40. Savva, A., Wustoni, S. & Inal, S. Ionic-to-electronic coupling efficiency in PEDOT:PSS films operated in aqueous electrolytes. J. Mater. Chem. C. 6, 12023–12030 (2018).10.1039/C8TC02195C ↗
41. Zhang, L. & Andrew, T. L. Deposition dependent ion transport in doped conjugated polymer films: insights for creating high‐performance electrochemical devices. Adv. Mater. Interfaces 4, https://doi.org/10.1002/admi.201700873 (2017).10.1002/admi.201700873 ↗
42. Wu, R., Paulsen, B. D., Ma, Q., McCulloch, I. & Rivnay, J. Quantitative composition and mesoscale ion distribution in p-type organic mixed ionic-electronic conductors. ACS Appl. Mater. Interfaces 15, 30553–30566 (2023).10.1021/acsami.3c04449 ↗
43. Murugappan, K. & Castell, M. R. Bridging electrode gaps with conducting polymers around the electrical percolation threshold. Electrochem. Commun. 87, 40–43 (2018).10.1016/j.elecom.2017.12.019 ↗
44. Janzakova, K. et al. Analog programing of conducting-polymer dendritic interconnections and control of their morphology. Nat. Commun. 12, 6898 (2021).10.1038/s41467-021-27274-9 ↗
45. Koizumi, Y. et al. Electropolymerization on wireless electrodes towards conducting polymer microfibre networks. Nat. Commun. 7, 10404 (2016).10.1038/ncomms10404 ↗
46. Ghazal, M. et al. Bio‐inspired adaptive sensing through electropolymerization of organic electrochemical transistors. Adv. Electron. Mater. 8, https://doi.org/10.1002/aelm.202100891 (2021).10.1002/aelm.202100891 ↗
47. Zhang, S. et al. Intrinsically antifouling, soft and conformal bioelectronic from scalable fabrication of thin-film OECT arrays by zwitterionic polymers. Chem. Eng. J. 483, https://doi.org/10.1016/j.cej.2024.148980 (2024).10.1016/j.cej.2024.148980 ↗
48. Rajapakse, R. M. G. et al. Implementing the donor-acceptor approach in electronically conducting copolymers via electropolymerization. RSC Adv. 12, 12089–12115 (2022).10.1039/D2RA01176J ↗
49. Musumeci, C., Hutchison, J. A. & Samori, P. Controlling the morphology of conductive PEDOT by in situ electropolymerization: from thin films to nanowires with variable electrical properties. Nanoscale 5, 7756–7761 (2013).10.1039/c3nr03093h ↗
50. Poverenov, E., Li, M., Bitler, A. & Bendikov, M. Major effect of electropolymerization solvent on morphology and electrochromic properties of PEDOT Films. Chem. Mater. 22, 4019–4025 (2010).10.1021/cm100561d ↗
51. Xie, M. et al. Cycling stability of organic electrochemical transistors. Org. Electron. 117, https://doi.org/10.1016/j.orgel.2023.106777 (2023).10.1016/j.orgel.2023.106777 ↗
52. Szumska, A. A. et al. Reversible electrochemical charging of n-type conjugated polymer electrodes in aqueous electrolytes. J. Am. Chem. Soc. 143, 14795–14805 (2021).10.1021/jacs.1c06713 ↗
53. Modarresi, M., Mehandzhiyski, A., Fahlman, M., Tybrandt, K. & Zozoulenko, I. Microscopic understanding of the granular structure and the swelling of PEDOT:PSS. Macromolecules 53, 6267–6278 (2020).10.1021/acs.macromol.0c00877 ↗
54. Li, Y. et al. Tailoring the self-healing properties of conducting polymer films. Macromol. Biosci. 20, e2000146 (2020).10.1002/mabi.202000146 ↗
55. Bargigia, I., Savagian, L. R., Osterholm, A. M., Reynolds, J. R. & Silva, C. Charge-transfer intermediates in the electrochemical doping mechanism of conjugated polymers. J. Am. Chem. Soc. 143, 294–308 (2021).10.1021/jacs.0c10692 ↗
56. Massonnet, N. et al. Improvement of the Seebeck coefficient of PEDOT:PSS by chemical reduction combined with a novel method for its transfer using free-standing thin films. J. Mater. Chem. C. 2, 1278–1283 (2014).10.1039/C3TC31674B ↗
57. Levi, M. D. et al. In situ porous structure characterization of electrodes for energy storage and conversion by EQCM-D: a review. Electrochim. Acta 232, 271–284 (2017).10.1016/j.electacta.2017.02.149 ↗
58. Easley, A. D. et al. A practical guide to quartz crystal microbalance with dissipation monitoring of thin polymer films. J. Polym. Sci. 60, 1090–1107 (2021).10.1002/pol.20210324 ↗
59. Reviakine, I., Johannsmann, D. & Richter, R. P. Hearing what you cannot see and visualizing what you hear: interpreting quartz crystal microbalance data from solvated interfaces. Anal. Chem. 83, 8838–8848 (2011).10.1021/ac201778h ↗
60. Kumar, P. et al. Effect of channel thickness, electrolyte ions, and dissolved oxygen on the performance of organic electrochemical transistors. Appl. Phys. Lett. 107, https://doi.org/10.1063/1.4927595 (2015).10.1063/1.4927595 ↗
61. Azimi, M., Subramanian, A., Roslan, N. A. & Cicoira, F. Flexible organic ion-gated transistors with low operating voltage and light-sensing application. J. Phys. 4, https://doi.org/10.1088/2515-7639/abd018 (2021).10.1088/2515-7639/abd018 ↗
62. King, Z. A., Shaw, C. M., Spanninga, S. A. & Martin, D. C. Structural, chemical and electrochemical characterization of poly(3,4-ethylenedioxythiophene) (PEDOT) prepared with various counter-ions and heat treatments. Polymer 52, 1302–1308 (2011).10.1016/j.polymer.2011.01.042 ↗
63. Boz, E. B., Fritz, M. & Forner‐Cuenca, A. Electropolymerized poly(3,4‐ethylenedioxythiophene) coatings on porous carbon electrodes for electrochemical separation of metals. Adv. Mater. Interfaces 10, https://doi.org/10.1002/admi.202202497 (2023).10.1002/admi.202202497 ↗