Enhancing reconstruction reaction kinetics by inner electric potential engineering for high-performance aqueous supercapacitors

For the materials with localized electronic structure characteristics, it is a significant challenge to enhance their reconstruction capabilities in the development of next-generation high-performance energy storage electrode materials. However, existing strategies overly emphasize the interaction between advantageous guest and host materials to achieve co-optimization of electronic structures, without addressing the intrinsic issues of the host material. Herein, we propose a novel concept of internal potential engineering, which aims to optimize the internal potential by directly adjusting the electronic structure of the host material. As a proof of concept, the charge distribution of Fe5Ni4S8 is directly modulated using surface groups, resulting in the optimization of Fe5Ni4S8 internal potential and significantly enhancing the intensity of its surface reconstruction reaction. Compared to unmodulated counterpart, the optimized Fe5Ni4S8 exhibits a high specific capacitance of 724.4 F/g at a current density of 1 A g (-1), and the assembled asymmetric supercapacitor achieves a maximum energy density of 41.35 Wh kg (-1). This study provides a promising pathway for the design of electrode materials with optimized dynamic reconstruction rates and high energy density.

Automated summary

This study proposes a novel concept of internal potential engineering, which aims to optimize the internal potential by directly adjusting the electronic structure of the host material. As a proof of concept, the charge distribution of Fe5Ni4S8 is modulated, resulting in the optimization of its internal potential and enhanced surface reconstruction reaction. The optimized material shows high specific capacitance and energy density, providing a promising pathway for the design of high-performance electrode materials.