Charge‐Compensated N‐Doped π‐Conjugated Polymers: Toward both Thermodynamic Stability of N‐Doped States in Water and High Electron Conductivity. Issue 31 (5th September 2022)

• Record Type: Journal Article
• Authors: Borrmann, Fabian; Tsuda, Takuya; Guskova, Olga; Kiriy, Nataliya; Hoffmann, Cedric; Neusser, David; Ludwigs, Sabine; Lappan, Uwe; Simon, Frank; Geisler, Martin; Debnath, Bipasha; Krupskaya, Yulia; Al‐Hussein, Mahmoud; Kiriy, Anton
• Is Part Of: Advanced science. Volume 9:Issue 31(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-05
• Subjects: density functional theory calculations -- electron conductivity -- n‐doped states -- thermodynamic stability -- π‐conjugated polymers; Science -- Periodicals; 505
• DOI: 10.1002/advs.202203530
• Languages: English
• ISSNs: 2198-3844

Abstract

Abstract: The understanding and applications of electron‐conducting π ‐conjugated polymers with naphtalene diimide (NDI) blocks show remarkable progress in recent years. Such polymers demonstrate a facilitated n‐doping due to the strong electron deficiency of the main polymer chain and the presence of the positively charged side groups stabilizing a negative charge of the n‐doped backbone. Here, the n‐type conducting NDI polymer with enhanced stability of its n‐doped states for prospective "in‐water" applications is developed. A combined experimental–theoretical approach is used to identify critical features and parameters that control the doping and electron transport process. The facilitated polymer reduction ability and the thermodynamic stability in water are confirmed by electrochemical measurements and doping studies. This material also demonstrates a high conductivity of 10 −2 S cm −1 under ambient conditions and 10 −1 S cm −1 in vacuum. The modeling explains the stabilizing effects for various dopants. The simulations show a significant doping‐induced "collapse" of the positively charged side chains on the core bearing a partial negative charge. This explains a decrease in the lamellar spacing observed in experiments. This study fundamentally enables a novel pathway for achieving both thermodynamic stability of the n‐doped states in water and the high electron conductivity of polymers. Abstract : This work focuses on electron‐conducting π ‐conjugated polymers with naphtalene diimide blocks bearing positively charged side groups. Studied polymers are characterized by enhanced stability of their n‐doped states for prospective "in‐water" applications and high election conductivity 10 −2 S cm −1 under ambient conditions. Using a combination of experimental and theoretical approaches, the authors explain the doping‐induced processes in thin polymer films.