Approaching Superfoldable Thickness-Limit Carbon Nanofiber Membranes Transformed from Water-Soluble PVA

Recent progress in flexible electronics has attracted tremendous attention. However, it is still difficult to prepare superfoldable conductive materials with good biocompatibility, high sensing sensitivities, and large specific surface areas. It is expected that biomimetic methods and water-soluble precursors like poly(vinyl alcohol) (PVA) for electrospinning will be utilized to solve the above problems. Inspired by the multistage water management process of a spider spinning dragline silk, we have established a combined biomimetic technique, hydrocolloid electrospinning coupled with temperature gradient dehydration, with a carbonization technique. PVA-driven superfoldable carbon nanofiber membranes (PVA-SFCNFMs) have been prepared that not only possess a >60% micropore ratio and a 1368.8 m(2)/g specific surface area but also can withstand 180 degrees real folding for 100 000 cycles, approaching the thickness limit without structure fracture. Furthermore, these membranes provide highly sensitive sensing and superior biocompatible interfaces. The molecular mechanism to improve carbon conversion and the folding mechanism to obtain three-level dispersing stress for the PVA-SFCNFMs have been proposed.

Automated summary

The study proposed a novel biomimetic technique combining electrospinning, temperature gradient dehydration, and carbonization to prepare superfoldable carbon nanofiber membranes. These membranes have high specific surface area, excellent biocompatibility, and sensitivity, and can withstand high-frequency real folding, providing a new research direction in the field of flexible electronics.