High Performance Sodium Ion Anodes Based on Sn_4P_3 Encapsulated within Amphiphilic Graphene Tubes

摘要

High-performance sodium-ion anode composites are synthesized through confined growth Sn4P3 nanoparticles within amphiphilic graphene tubes, which provide mechanical robustness, the ability to confine Sn4P3 particles with their highly conductive frameworks, and the capability to accommodate the volume change of the particles during cycling. This unique structure endows a sodium-ion anode with high reversible capacity (821 mA h g(-1)), excellent rate capability (326 mA h g(-1) at 20 A g(-1)), and cycling stability (90% reversible capacity retention after 500 cycles). This strategy can be extended to other conversion- and alloying-type materials that experience dramatic volume change during charging and discharging.