Hydrogen bond-mediated polar structure engineering of PVDF toward superior energy storage

Dielectric capacitors have emerged as a pivotal class of energy storage devices in modern electronics. A major challenge is that their low volumetric energy density hinders further development. To address this challenge, all-organic films have gained attention as a promising and scalable alternative. Here, we developed an all-organic xylitol–PVDF film, which maximizes energy density by constructing a hydrogen bond network between PVDF and xylitol. The network enhances the crystallinity of PVDF, reduces the grain size of the α phase, β phase and γ phase, and increases the β phase content. The xylitol–PVDF composite film containing 5 wt% xylitol demonstrates a remarkable energy density of 23.64 J cm⁻³ and an impressive charge–discharged efficiency of 84.2%. This work provides a facile and scalable approach for fabricating high-performance PVDF-based dielectric films that demonstrate exceptional energy storage performance.