Supported by the National Natural Science Foundation of China (Grant Nos. 52388201, 52102177, 52472125), an international research team led by Prof. Weiwei Li from Nanjing University of Aeronautics and Astronautics, and Prof. Ce-Wen Nan from Tsinghua University, has made significant progress in ultrahigh capacitive energy storage. This research, titled “Ultrahigh capacitive energy storage through dendritic nanopolar design” was published in Science on April 11, 2025 (https://www.science.org/doi/10.1126/science.adt2703).

Dielectric capacitors, as the fundamental energy storage component in high-power pulse technology, hold significant strategic value in advanced technological fields, including ultra-high-power devices. However, the low energy density of dielectric capacitors is a key bottleneck limits their wider application. Developing new dielectric materials with high energy density and high efficiency is not only a necessary path to miniaturize and modularize energy storage components, but also an important step in breaking the development bottlenecks in the power electronics field. This has become one of the key frontier directions in the field of materials physics and materials science.

The research team innovatively developed a three-dimensional self-assembled dendritic nanocomposite structure design strategy, effectively overcomes the traditional trade-off between polarization strength and dielectric breakdown strength. This approach significantly enhances the energy storage density and reliability of capacitor devices. Theoretical analysis and experimental research show that the three-dimensional dendritic network can effectively block the breakdown channel. The ferroelectric phase in the dendritic structure induces the formation of rhombohedral/tetragonal nanodomains, resulting in strong relaxor features, high saturation polarization and low remanent polarization, accompanied by the occurrence of antiferroelectric-like behavior and a significant reduction in leakage current density. Collectively, this work achieves an ultrahigh energy density of 215.8 J/cm³ with an efficiency of 80.7%. In addition, the dielectric capacitor also exhibits excellent cycle stability (10¹⁰ cycles), temperature stability (less than 6% fluctuation in the range of -100 ~ 170ºC), and rapid discharge response characteristics (discharge response time 3.3 ms).

This work challenges the traditional theoretical framework for optimizing single-phase dielectric materials, addressing the challenge of simultaneously improving polarization strength and breakdown field strength.  It provides both theoretical and technical support for developing the dielectric energy storage devices with higher energy storage density, higher energy efficiency and faster discharge response.

Figure: (A) Schematic diagram of three-dimensional self-assembled dendritic nanocomposite structure. (B) Three-dimensional self-assembled dendritic nanocomposite structure composed of ferroelectric-wide bandgap insulator. (C) Comparison of the energy density and breakdown strength of this work with literatures.