摘要
The crystal structure of PVDF is regulated by phase regulation engineering, which optimizes the ion transport kinetics and improves the interface compatibility of electrolytes. • The introduction of PMMA reduced the binding energy between polymers and ions from 52 to 16 kJ·mol -1 , which enhanced the migration movement of ions. • The optimized PVDF/PMMA iongel electrolyte achieves a high ionic conductivity of 4.115 mS cm -1 via a continuous ion diffusion pathway. The ion transport kinetics in poly(vinylidene fluoride) (PVDF)-based ion-gel polymer electrolytes (IGPEs) are limited by the polymer's high crystallinity and intrinsic phase separation, which impede ion dissociation and diffusion in supercapacitors. Herein, poly(methyl methacrylate) (PMMA) is incorporated into the PVDF matrix containing 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF 4 ), which effectively disrupts crystalline domains and mitigates phase separation, establishing a homogeneous amorphous architecture with percolated ion migration pathways. Combined experimental and theoretical analyses reveal that PMMA reduces the polymer-ionic liquid binding energy, promoting ion-pair dissociation and increasing free charge carrier concentration. The optimized IGPE exhibits an enhanced ionic conductivity of 4.115 mS cm -1 and it achieved a specific capacitance of 39.01 F g -1 at 0.1 A g -1 . Meanwhile, its rate capability and cycling stability are optimized. DFT and MD calculations further confirm that PMMA weakens the Coulombic association between BMIM + and BF 4 - ions and enhances their self-diffusion coefficients, thus accelerating overall ion transport. This work provides fundamental insights into the ion transport mechanism of ionic liquid-based IGPEs, offering valuable guidance for the rational design of high-performance solid gel electrolytes. Download: Download high-res image (417KB) Download: Download full-size image
危险品化学品经营许可证（带存储）