Dataset of "Development of Renewable Flexible Supercapacitors: Tailoring Polypyrrole Nanotube/Carbonaceous Filler-Based Electrodes and Cellulose Hydrogel Electrolytes for Enhanced Electrochemical Performance"

The growing demand for sustainable and high-performance energy storage solutions has driven advancements in flexible supercapacitors, known for their high power density, fast charging, and mechanical adaptability. This study explores the fabrication of novel flexible and lightweight electrodes using one-pot and two-step synthesis approaches tailored for supercapacitor applications. These methods integrate polypyrrole nanotubes (PPy–NT) as pseudocapacitive materials, cellulose nanofibers (CNF) as a flexible matrix, and nitrogen-doped 1D carbonaceous fillers (ACT–NT) as electric double-layer capacitance (EDLC) material. The ACT–NT are produced through carbonization and activation of PPy–NT. To construct a renewable and flexible supercapacitor, cellulose hydrogel electrolyte offering flexibility, stability, and non-leakage properties was prepared using a simple, and highly reproducible methodology. This study demonstrates that PPy–NT/CNF electrodes outperform those with carbonaceous fillers during initial GCD cycles in both two- and three-electrode setups. However, electrodes containing carbonaceous fillers show superior capacity retention over extended GCD cycling, especially within larger potential windows. This improvement is attributed to the high specific surface area of the carbonaceous fillers and the efficient electrolyte accessibility to their microporous/mesoporous structure, which enhances EDLC. Notably, while nitrogen doping of the carbonaceous fillers enhance the dispersion, wettability, and compatibility between the components, it has only minimal impact on overall electrochemical performance of the electrode. In contrast, the electrode fabrication method significantly influences the electrochemical performance. Specifically, PPy–NT/ACT–NT@1000/CNF_TS1-1, prepared via two-step synthesis, outperforms its one-pot synthesis counterpart (PPy–NT/ACT–NT@1000/CNF) due to an optimized balance of electrical conductivity, morphology, wettability, and textural properties, resulting in superior electrochemical performance.