Single Zn atoms anchored on hollow carbon nanofiber network for dendrite-free lithium metal anode of flexible Li-S full cell

Abstract: The attractive energy density of lithium-sulfur (Li-S) batteries makes them desirable energy storage systems; however, the slow reaction kinetics and formation of lithium dendrites prevent them from reaching full potential. To address this issue, hierarchical porous carbon nanofibers network containing Zn single atoms (ZnSA@HPCNF) is synthesized by electrospinning and carbonization. This structure serves as the main anode body, providing excellent chemical anchoring and lipophilicity. The uniform distribution of Zn single atoms and N4 coordination supports uniform deposition and continuous plating/stripping of lithium. The results show that the Li|Li/ZnSA@HPCNF symmetrical battery presents stable and low overpotential during 700- and 900-h iterative plating/stripping process at 1 and 5 mA·cm−2, respectively. Furthermore, the S/CNT||Li/ZnSA@HPCNF full cell shows good flexibility, reversible capacity and cycling stability. This work provides a lithium host strategy based on single-atom dispersed hierarchical porous carbon network, enabling the design of rational lithium metal anodes for use in flexible Li-S full cells. Graphical abstract: [Figure not available: see fulltext.]