All-in-One MoS₂ Nanosheets Tailored by Porous Nitrogen-Doped Graphene for Fast and Highly Reversible Sodium Storage

Abstract

Though being a promising anode material for sodium-ion batteries (SIBs), MoS₂ with high theoretical capacity shows poor rate capability and rapid capacity decay, especially involving the conversion of MoS₂ to Mo metal and Na₂S. Here, we report all-in-one MoS₂ nanosheets tailored by porous nitrogen-doped graphene (N-RGO) for the first time to achieve superior structural stability and high cycling reversibility of MoS₂ in SIBs. The all-in-one MoS₂ nanosheets possess desirable structural characteristics by admirably rolling up all good qualities into one, including vertical alignment, an ultrathin layer, vacancy defects, and expanded layer spacing. Thus, the all-in-one MoS₂@N-RGO composite anode exhibits an improvement in the charge transport kinetics and availability of active materials in SIBs, resulting in outstanding cycling and rate performance. More importantly, the restricted growth of all-in-one MoS₂ by the porous N-RGO via a strong coupling effect dramatically improves the cycling reversibility of conversion reaction. Consequently, the all-in-one MoS₂@N-RGO composite anode demonstrates excellent reversible capacity, outstanding rate capability, and superior cycling stability. This study strongly suggests that the all-in-one MoS₂@N-RGO has great potential for practical application in high-performance SIBs.