INS6-1674
Engineering Biopolymer-Derived Interfaces and Carbons for High-Performance Sustainable Zinc-Based Energy Storage
Topic
S6. Emerging Polymer and Hybrid Materials for Advanced Energy Storage and Conversion
When and Where
Oct 1, 2026
11:10 - 11:35
Room 311 & 312
Session Chairs
Soochan KIM
Presenter(s)
Mahiar Max HAMEDI (KTH Royal Institute of Technology)
Co-Author(s)
Abstract
The transition toward sustainable rechargeable batteries requires not only high electrochemical performance, but also electrode materials derived from abundant, non-toxic, and renewable resources. Aqueous zinc-ion hybrid capacitors (ZICs) are particularly promising in this context, combining a high-capacity metallic Zn anode with capacitor-type cathodes and intrinsically safer, water-based electrolytes. However, their practical performance remains constrained by limited cathode capacity, complex Zn²⁺/H⁺ interfacial processes, and degradation mechanisms that are poorly understood at the microscopic level. Here, we demonstrate how biopolymer-derived electrode components can be rationally engineered by resolving ion transport, adsorption, and degradation processes under realistic electrochemical conditions.
First, we investigate the often-overlooked role of polymer binders in controlling the electrode–electrolyte interface. Poly(vinylidene fluoride) (PVDF), cellulose acetate (CA), and carboxymethyl cellulose (CMC) are systematically compared as binders with contrasting hydrophilicity and interfacial chemistry. By combining in-situ electrochemical quartz crystal microbalance (EQCM), pulsed-field-gradient nuclear magnetic resonance (PFG-NMR), and electrochemical kinetic analysis, we establish correlations between binder chemistry, Zn²⁺ transport, electrolyte accessibility, and interfacial charge-storage behavior. The results demonstrate that the binder is not simply a mechanically inactive component, but actively defines the microscopic environment through which solvated ions must migrate and interact with the porous carbon surface. This provides a route toward replacing conventional fluorinated binders with cellulose-derived biopolymers designed as functional ion-regulating interfaces.
We further extend this concept from biopolymer binders to biopolymer-derived active materials using lignin-derived porous carbons. Through an integrated operando platform combining EQCM, pH monitoring, online electrochemical mass spectrometry (OEMS), and advanced electrochemical analysis, we decouple the structural origins of capacity and degradation. Surprisingly, Zn-ion adsorption in micropores accounts for only approximately 28% of the total capacity, while proton-coupled processes dominate substantial portions of charge storage. EQCM mass-to-charge and dissipation-to-charge relationships further distinguish cation/anion adsorption regimes and reveal zinc hydroxyl sulfate formation, electrolyte dragging, and pore blocking in real time. Meanwhile, 2–4 nm mesopores accelerate ion transport and improve high-rate performance, yet can adversely affect low-rate behavior, demonstrating that maximizing surface area or mesoporosity alone does not necessarily maximize usable capacity.
Together, these studies establish a multiscale framework in which biopolymers serve both as functional electrode components and renewable precursors for advanced carbon materials. By connecting molecular-scale ion transport and interfacial chemistry with pore-scale charge storage and degradation, we move beyond empirical materials optimization toward mechanistically guided electrode design. The results highlight a pathway toward future aqueous Zn-based energy-storage technologies in which renewable cellulose- and lignin-derived materials can simultaneously improve sustainability, regulate electrochemical interfaces, and enable high-performance rechargeable energy storage.
First, we investigate the often-overlooked role of polymer binders in controlling the electrode–electrolyte interface. Poly(vinylidene fluoride) (PVDF), cellulose acetate (CA), and carboxymethyl cellulose (CMC) are systematically compared as binders with contrasting hydrophilicity and interfacial chemistry. By combining in-situ electrochemical quartz crystal microbalance (EQCM), pulsed-field-gradient nuclear magnetic resonance (PFG-NMR), and electrochemical kinetic analysis, we establish correlations between binder chemistry, Zn²⁺ transport, electrolyte accessibility, and interfacial charge-storage behavior. The results demonstrate that the binder is not simply a mechanically inactive component, but actively defines the microscopic environment through which solvated ions must migrate and interact with the porous carbon surface. This provides a route toward replacing conventional fluorinated binders with cellulose-derived biopolymers designed as functional ion-regulating interfaces.
We further extend this concept from biopolymer binders to biopolymer-derived active materials using lignin-derived porous carbons. Through an integrated operando platform combining EQCM, pH monitoring, online electrochemical mass spectrometry (OEMS), and advanced electrochemical analysis, we decouple the structural origins of capacity and degradation. Surprisingly, Zn-ion adsorption in micropores accounts for only approximately 28% of the total capacity, while proton-coupled processes dominate substantial portions of charge storage. EQCM mass-to-charge and dissipation-to-charge relationships further distinguish cation/anion adsorption regimes and reveal zinc hydroxyl sulfate formation, electrolyte dragging, and pore blocking in real time. Meanwhile, 2–4 nm mesopores accelerate ion transport and improve high-rate performance, yet can adversely affect low-rate behavior, demonstrating that maximizing surface area or mesoporosity alone does not necessarily maximize usable capacity.
Together, these studies establish a multiscale framework in which biopolymers serve both as functional electrode components and renewable precursors for advanced carbon materials. By connecting molecular-scale ion transport and interfacial chemistry with pore-scale charge storage and degradation, we move beyond empirical materials optimization toward mechanistically guided electrode design. The results highlight a pathway toward future aqueous Zn-based energy-storage technologies in which renewable cellulose- and lignin-derived materials can simultaneously improve sustainability, regulate electrochemical interfaces, and enable high-performance rechargeable energy storage.
