Silanized palygorskite clay as a template for the preparation of polypyrrole-based nanocomposites for supercapacitor electrodes

• Published in: Journal of materials science. Materials in electronics 2024-06, Vol.35 (18), p.1262, Article 1262
• Main Authors: Díaz-Arriaga, Carlos Bellaner, Baas-López, José Martin, Uribe-Calderón, Jorge Alonso, Pacheco-Catalán, Daniella Esperanza
• Format: Article
• Language: English
• Subjects: Capacitance; Characterization and Evaluation of Materials; Chemical synthesis; Chemistry and Materials Science; Clay; Coupling agents; Cycles; Electrical resistivity; Electrochemical analysis; Electrode materials; Electrodes; Materials Science; Nanocomposites; Nanostructured materials; Optical and Electronic Materials; Polypyrroles; Sheaths; Stability; Supercapacitors; Synergistic effect
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-024-12956-z

Polypyrrole (PPy) is considered a promising electrode material for supercapacitors (SCs) due to its high specific capacitance; however, it exhibits low long-term cycling stability. To address this issue, the introduction of nanostructured materials into the PPy matrix yields nanocomposites that exhibit enhanced capacitance and improved cycling stability. In this study, PPy/palygorskite (PPy/Pal) nanocomposites were synthesized via in situ chemical polymerization of pyrrole on Pal templates. To enhance the compatibility between PPy and the clay, the surface of Pal was modified with a silane coupling agent (Pal-S). In a half-cell configuration, the PPy/Pal-S electrodes exhibit better electrochemical performance in terms of specific capacitance, rate capability, and cycling stability than the PPy electrode. The PPy/Pal-S nanocomposites achieved a maximum specific capacitance of 218 F g −1 and retained 91% of their initial capacitance after 500 CV cycles. Moreover, the fabricated symmetric supercapacitor device elaborated with the PPy/Pal-S electrodes delivered a specific capacitance of 15 F g −1 at 3 mA cm −2 , an energy density of 0.9 Wh kg −1 , a power density of 55 W kg −1 with a cycling stability of 72% after 2000 GCD cycles, in a voltage range of 0.7 V. This study presents a novel strategy for constructing a 1D core/sheath PPy/Pal-S structure, which combines the advantageous properties of PPy (pseudocapacitance and electrical conductivity) and Pal-S clay (mechanical and chemical stability, 1D morphology, mesoporosity, and nanoscale size). Understanding the synergistic effects provides valuable insights for designing electrode materials with superior performance.