TY - JOUR
T1 - Synthesis, Voltammetry, and Spectroelectrochemical Characterization of Tunable Ferrocene-Jeffamine Redox-Active (Co)polymers
T2 - Controlling Redox and Ionic Interactions Through Composition
AU - Ibrahim, Nafisa A.
AU - N'Diaye, Jeanne
AU - Romo, Adolfo I.B.
AU - Gaddam, Raghuram
AU - Zimmerman, Steven C.
AU - Rodríguez-López, Joaquín
N1 - Publisher Copyright:
© 2025 American Chemical Society.
PY - 2025/4/8
Y1 - 2025/4/8
N2 - There is a critical need for predictably modulating the reactivity of redox-active polymers (RAPs) to improve their performance in applications such as catalysis, energy storage, and sensing. However, few studies systematically modify the redox loading through copolymerization to understand the impact on the polymer electrochemistry. In this study, we developed a series of (co)polymers incorporating redox-active ferrocene motif and nonredox-active, polyethylene glycol-type Jeffamine diluent, using ring-opening metathesis polymerization (ROMP). The redox activity and charge transfer characteristics of the resulting (co)polymers were successfully modulated by systematically varying the ratios of the two monomers, where elemental analysis and ultraviolet-visible (UV-vis) spectroscopy quantitatively confirmed their composition. Cyclic voltammetry (CV) analysis of films deposited and operated in different conditions for samples synthesized with 25% to 100% of the ferrocene repeat unit confirmed the ability to fine-tune redox behavior, including interchain interactions. Furthermore, experiments at varying ionic strength and (co)polymer composition revealed distinct interactions with ions in the supporting electrolyte, as probed via in situ infrared spectroscopy. The behavior of polymers in solution, characterized via bulk electrolysis and UV-vis spectroscopy, was compared to that in films, highlighting the role of Jeffamine in decreasing interactions responsible for distortions in the film CV and polymer insolubility in their oxidized form. This approach of incorporating nonredox-active monomers to modulate redox and ionic interactions could be applied to other combinations of polymers and redox-active molecules, offering a strategic approach to tailor properties such as solubility, charge accessibility, and rate in redox polymers for diverse applications.
AB - There is a critical need for predictably modulating the reactivity of redox-active polymers (RAPs) to improve their performance in applications such as catalysis, energy storage, and sensing. However, few studies systematically modify the redox loading through copolymerization to understand the impact on the polymer electrochemistry. In this study, we developed a series of (co)polymers incorporating redox-active ferrocene motif and nonredox-active, polyethylene glycol-type Jeffamine diluent, using ring-opening metathesis polymerization (ROMP). The redox activity and charge transfer characteristics of the resulting (co)polymers were successfully modulated by systematically varying the ratios of the two monomers, where elemental analysis and ultraviolet-visible (UV-vis) spectroscopy quantitatively confirmed their composition. Cyclic voltammetry (CV) analysis of films deposited and operated in different conditions for samples synthesized with 25% to 100% of the ferrocene repeat unit confirmed the ability to fine-tune redox behavior, including interchain interactions. Furthermore, experiments at varying ionic strength and (co)polymer composition revealed distinct interactions with ions in the supporting electrolyte, as probed via in situ infrared spectroscopy. The behavior of polymers in solution, characterized via bulk electrolysis and UV-vis spectroscopy, was compared to that in films, highlighting the role of Jeffamine in decreasing interactions responsible for distortions in the film CV and polymer insolubility in their oxidized form. This approach of incorporating nonredox-active monomers to modulate redox and ionic interactions could be applied to other combinations of polymers and redox-active molecules, offering a strategic approach to tailor properties such as solubility, charge accessibility, and rate in redox polymers for diverse applications.
UR - http://www.scopus.com/inward/record.url?scp=105002326305&partnerID=8YFLogxK
U2 - 10.1021/acs.macromol.4c02501
DO - 10.1021/acs.macromol.4c02501
M3 - Article
AN - SCOPUS:105002326305
SN - 0024-9297
VL - 58
SP - 3665
EP - 3676
JO - Macromolecules
JF - Macromolecules
IS - 7
ER -