Investigation on the Performance of Carbon Nanotube-Doped Polypyrrole Flexible Supercapacitor Electrodes via Gamma-Ray Irradiation Modification

Flexible supercapacitors have surged in popularity across various sectors, including artificial intelligence (AI), wearable technology, and renewable energy. In this work, carbon nanotubes (CNTs) submerged in an organic solution of pyrrole (Py) monomer were exposed to gamma-ray irradiation to create carbon nanotubes doped polypyrrole (CNTs/PPy) flexible supercapacitor electrode materials. Scanning electron microscopy (SEM) was used to characterize the surface microstructure of electrode materials before and after irradiation, and the formation and adhesion of new substances on the material surface and CNTs was found, which was hypothesized that gamma-ray irradiation initiated the polymerization reaction of Py monomers and the production of polypyrrole (PPy). Additional examination of the electrode materials using Fourier transform infrared absorption spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) verified the successful advancement of the polymerization reaction and the formation of PPy conductive polymer. The prepared CNTs (5 mg)/PPy electrode materials exhibited excellent electrochemical properties, with a specific capacitance of 201.6 F g–1. The constant current charge-discharge (GCD) and alternating current impedance spectroscopy (EIS) experiments of electrode materials confirmed that the loading of CNTs effectively improved the conductivity and electrochemical stability of the material, reduced the resistivity, and demonstrated a positive effect on improving the electrochemical performance of the material. However, it was also observed that an overabundance of CNTs compromised the mechanical properties and flexibility of the material. Overall, our findings provide valuable insights and a benchmark for developing flexible supercapacitor electrode materials with enhanced electrochemical performance.