Dual carbon modification of few-layered ReS2 nanosheets to retard polysulfide shuttling for long-cycling sodium-ion batteries

Abstract

Rhenium disulfide (ReS2) is promising to work as a robust host for sodium storage, owing to the extremely weak interlayer van der Waals interactions and large interlayer spacing. However, the low electronic conductivity and huge volume expansion seriously restrict high-rate capability and cycling lifespan. In this work, few-layered ReS2 nanosheets with carbon coating (ReS2/C) grown on the hollow mesoporous carbon spheres (HMCS) are designed to form the HMCS@ReS2/C architectures that have several merits for the sodium storage, attributed to the dual carbon modification and the hollow structure. (i) HMCS provides a large interior void to relieve the volume change during discharge/charge processes and superior structural stability for long-term cycling. (ii) The large hetero-interfacial contact can enhance electron/Na+ transport in ReS2, enabling accelerated reaction kinetics. (iii) The outer carbon layer formed on ReS2 surface is capable of inhibiting dissolution of polysulfide ions and their corrosion to the copper current collector, preventing the “under-voltage failure” phenomenon. Consequently, HMCS@ReS2/C delivers superior sodium storage performance, yielding excellent high-rate capability (211 mAh g−1 at 10 A g−1), long lifespan (4000 cycles at 10 A g−1) and stable cycling stability with an extremely low capacity decay rate of 0.0096% per cycle. The high-rate cyclability surpasses the record of ReS2-based anodes reported previously. Furthermore, the fabricated Na3V2(PO4)3║HMCS@ReS2/C full cells can also exhibit outstanding cycling performance.

Keywords

• Sodium-ion batteries
• ReS2
• Dual carbon modification
• Ether-based electrolytes
• Shuttle effect