Novel Polymer Sulfurization for Enhanced Electrochemical Performance in Lithium-Sulfur Cathodes

Sulfurized Polyacrylonitrile, SPAN, shows high electrochemical stability in lithium-sulfur batteries. Our prior work on SPAN indicated the unique role of nitrogen in modifying the quantum capacitance of an electrode. Here, we present a comprehensive investigation of the electrochemical performance of sulfurized polymers, including nylon, polystyrene, polyaniline, and polypropylene. The different sulfurized polymers provide insight into controlling the nitrogen:sulfur ratios while keeping the synthesis method consistent. This talk will discuss the challenges involved in preparing stable sulfurized polymer electrodes with varying nitrogen to sulfur ratios and present the effects of synthesis procedures on the final electrochemical performance. By using a range of analytical techniques, including Scanning Electron Microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), Cyclic Voltammetry (CV), Charge-Discharge cycling, x-ray photoemission (XPS), we gained deeper insights into the mechanisms in sulfurized electrodes. In combining the insights gained from the analytical techniques, the synthesis methods, and the electrochemical performance across the polymers, we present a conclusive idea of the importance of quantum capacitance in energy storage.