Rationally designed polyhedral carbon framework from solid to hollow for long cycle life secondary batteries

Abstract

In order to better meet the energy demand of rapidly developing electronic devices, it is urgent to develop electrode materials with high capacity and stability. In this article, we report a polyhedral carbon framework, which can evolve from a solid to hollow structure through rational design. Thanks to a good hollow, porous and thin shell structure, the material can be used for lithium–sulfur batteries (LSBs) and lithium/sodium ion batteries. For the lithium/sodium storage process, the capacity can be stabilized at 333.3 mA h g⁻¹ (1000)/150.4 mA h g⁻¹ (2000), even at a high current density of 10.0 A g⁻¹. In addition, this unique material can also be used to modify commercial PP separators, which provides huge benefits to LSBs. The synergistic adsorption of polysulfides is achieved through physical/chemical interactions. It can provide a 625.4 mA h g⁻¹ reversible capacity after 1000 cycles at a current density of 1.0C, and the capacity decay rate is as low as 0.046%. At the same time, this excellent cycle stability can be maintained under extremely high sulfur loading conditions. The sharing of this work emphasizes the importance of rational design of nanostructures for improving the cycle performance of secondary batteries.