Observation on Sodium p-Toluenesulfonate Doped Polypyrrole Cathode for Sodium Ion Battery

Abstract

Sodium p-toluenesulfonate (TsONa)-doped polypyrrole (PPy) was synthesized as the cathode active material of sodium ion battery by way of facile one-step electrodeposition on iron (Fe) foil. The micro-morphology and micro-structure of assynthesized TsONa/PPy/iron cathode were characterized in terms of scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction; furthermore, the electrochemical Na-storage activity of TsONa/PPy/iron cathode was investigated by methods of, galvanostatic charge/discharge, cyclic voltammetry and alternating current impedance. As expected, the cauliflower-like TsONa-doped PPy particles tightly combined with the surface of the iron foil without any additional polymer binders; and also, the resultant TsONa/PPy/iron cathode delivered satisfactory electrochemical performances, mainly attributed to high Na-storage activity of PPy matrix and high electronic conductivity induced by doping of TsONa. For example, the reversible discharge capacity of TsONa/PPy/iron cathode remained about 98 mAh/g after at least 50 cycles and the corresponding coulombic efficiency was 92%, indicating high cyclic stability and reversibility of TsONa/PPy/iron cathode for sodium ion battery.

Conducting Polymers for Sodium-Ion Batteries

“…However, when conducting polymers were directly used as cathodes in SIBs, they would react with large electrolyte anions via a p-doping/de-doping mechanism, leading to a poor capacity utilization of the polymer chains [39]. In order to solve this problem, one strategy appeared recently which is doping some ionizable groups in the conducting polymers to change the redox reaction mechanism from conventional p-doping/de-doping processes of large electrolyte anions to the insertion-extraction reactions of small cations (Na ions) [39][40][41][42][43][44][45][46][47].…”

ZnCo2O4 Nanorods Coated with Annealed Polypyrrole/Poly(vinyl alcohol) Composites as Anode Materials for Lithium-Ion Batteries

“…Constructing ZnCo 2 O 4 nanostructures with electrically conductive materials could mitigate the drastic capacity fade. The addition of polypyrrole (PPy) enhances the electrode performance due to its low oxidation potential and high conductivity. − However, there are still several limitations to be addressed prior to mass production of ZnCo 2 O 4 /PPy nanocomposites, such as the aggregation of PPy nanoparticles, , the difficulty of tightly combining the matrix and PPy, and the difficulty of forming a complete three-dimensional coating. One effective approach to overcome these drawbacks is to obtain reasonable control of the PPy layer to achieve desirable nanostructures that significantly enhance the capacitance and cyclic performance …”