Effect of Acrylonitrile Composition in NBR on Enhanced Anion Doping-Undoping Process of NBR-Guided-Grown-Polypyrrole Film Electrode

The anion doping-undoping process of NBR (nitrile butadiene rubber)-guided-grown-polypyrrole (PPy/NBR) film electrode was investigated by varying the precoated NBR film thickness and the acrylonitrile content in the NBR host polymer. The electrode kinetics and the morphology orientation of the PPy/NBR film were found to depend greatly on the nature of the precoated NBR film. Compared to a normally polymerized PPy film, a PPy/NBR film formed particularly with ClO₄⁻ anion showed an enhanced switching reversibility and an acceleration of the dopant movement within the polymer layer. Impedance analysis revealed that the PPy/NBR films show a clear change in their overall electrode process, from a charge transfer limiting process to a diffusion limiting process according to an increase in the precoated NBR thickness and also to a decrease in the acrylonitrile content of the NBR film. The perpendicularly formed morphology is easily formed when using NBR with less acrylonitrile. The rechargeable lithium battery with a PPy/NBR cathode shows a better charging-discharging performance than a PPy/NBR cathode formed with a lower AN content NBR.