Ultrafast lithium energy storage enabled by interfacial construction of interlayer-expanded MoS ₂/N-doped carbon nanowires

Abstract

Edge-oriented and interlayer-expanded MoS ₂ nanosheets/N-doped carbon nanowires are prepared and exhibit ultrafast and durable Li ⁺ storage performance.

Abstract

Two-dimensional (2D) molybdenum disulfide (MoS ₂) has been extensively regarded as a promising host material for lithium ion batteries due to the reversible insertion of Li ⁺ into the layered structures. However, achieving ultrafast and durable Li ⁺ storage has a challenge of designing largely exposed edge-oriented and kinetically favorable MoS ₂-based nanostructures. Herein, we report an interfacial synthesis strategy for facile construction of ultrathin MoS ₂/N-doped carbon nanowires (MoS ₂/N–C NWs) ( ca. 10 μm in length) with a largely expanded (002) plane of MoS ₂ ( d = 1.03 nm, vs. bulk 0.62 nm). This hierarchical nanowire configuration composed of edge-oriented and interlayer-expanded MoS ₂ nanosheets can not only effectively decrease the diffusion energy barriers for Li ⁺ intercalation and improve the number of electrochemically active sites, but also provide fast electron pathways. As an anode for LIBs, the MoS ₂/N–C NWs demonstrate excellent rate capabilities (600 mA h g ⁻¹ at 5 A g ⁻¹ and 453 mA h g ⁻¹ at 10 A g ⁻¹) and long-term durability (86.7% retention at 5 A g ⁻¹ over 500 cycles). This study demonstrates the great potential of the MoS ₂/N–C NWs as promising anode materials for ultrafast lithium energy storage.