Ultrahigh-energy-density dielectric materials from ferroelectric polymer/glucose all-organic composites with a cross-linking network of hydrogen bonds

Polymer dielectrics have been widely used for capacitive energy storage. However, the volumetric energy density of polymer dielectrics is generally low, which falls short of the need for high-power and compact-size electronic devices and electrical systems. Here, a scalable all-organic composite based on a ferroelectric polymer incorporated with an abundant, cost-effective organic molecule, i.e., glucose is reported, exhibiting record dischargeable energy density (37.7 J/cm3) that outperforms the state-of-the-art dielectric polymer composites. The glucose molecules rich in hydroxyl groups are found to facilitate the formation of a physically cross-linking network of hydrogen bonds within the polymer matrix, which is responsible for the remarkable performance improvement. Both simulation and experimental results show that the hydrogen bonds serve as the trapping sites of charge carriers and suppress conduction loss. The hydrogen bond network is also found to account for the increased crystallinity, reduced crystallite size, and stabilized γ phase in the polymer, which leads to enhanced electric displacement and reduced hysteresis loss. In combining the advantages of extraordinary energy storage performance, abundant raw materials, ease of preparation, this approach is viable for large-scale production of polymer-based high-energy-density dielectric materials.