ORS10-1669
Simulating Concerted Ion Injection and Doping in Organic Electrochemical Transistors
Topic
S10. AI-assisted Design and Simulation of Polymers
When and Where
Sep 29, 2026
16:15 - 16:30
Room 109
Session Chairs
Lisa HALL
Presenter(s)
Kyeong-jun Jeong (Kyonggi University)
Co-Author(s)
Abstract
Organic electrochemical transistors (OECTs) rely on volumetric doping, in which ion injection from the electrolyte and oxidation of the conjugated polymer backbone occur as a concerted electrochemical process [1]. However, classical all-atom molecular dynamics (MD) simulations conventionally assign a fixed, initially charge-neutral force field to the polymer, offering an insufficient representation of this concerted doping driving force. In this talk, we present an iterative oxidation protocol for all-atom MD simulation that captures the coupled ion-injection and doping process at OECT-relevant polymer-electrolyte interfaces. At each iteration, dopant-induced oxidation is assigned to conjugated monomers according to a thermodynamic probability model based on the free energy of oxidation, followed by structural relaxation, allowing the film to evolve toward a steady-state doped structure under applied voltage. Using this protocol, we compare polymer side-chain designs and show that dopant ion accessibility to the conjugated backbone, rather than the total ion uptake into the film, governs the resulting charge carrier density. These simulated trends in backbone-ion proximity and doping efficiency are corroborated by experimental measurements of capacitance and doping efficiency across a series of conducting polymers [2]. Our results demonstrate that explicitly incorporating the concerted, voltage-driven nature of doping into nanoscale MD simulations is essential for rationalizing side-chain design strategies in OECT materials.
References
[1] J. Rivnay, S. Inal, A. Salleo, R. M. Owens, M. Berggren, and G. G. Malliaras, Nat. Rev. Mater. 2018, 3, 17086.
[2] W. J. Pyo, K.-J. Jeong, J. Shanahan, J. Neu, J. Kim, X. Zhong, C. Y. Son, W. You, and D. S. Chung, Nat. Commun. 2026, 17, 8644.
[1] J. Rivnay, S. Inal, A. Salleo, R. M. Owens, M. Berggren, and G. G. Malliaras, Nat. Rev. Mater. 2018, 3, 17086.
[2] W. J. Pyo, K.-J. Jeong, J. Shanahan, J. Neu, J. Kim, X. Zhong, C. Y. Son, W. You, and D. S. Chung, Nat. Commun. 2026, 17, 8644.
