Rationally designed bulky MoS2@C@MoS2 hierarchical materials as an enhanced anode for lithium-ion batteries

Abstract

The hierarchical material integrates the advantages of each component and is an ideal structure for efficiently storing lithium ions. However, constructing hybrid structures with excellent physical/electrochemical properties, notably bulky natural minerals, remains challenging. Herein, the precursor decomposition method built a bulky three-layer MoS₂@C@MoS₂ hierarchical materials. Ultrathin MoS₂ nanoarrays grow vertically on the surface of nitrogen-doped carbon-coated expanded molybdenite (MoS₂@C). MoS₂ nanosheets and bulky expanded molybdenite have the same composition, which is beneficial for reducing side reactions. MoS₂ nanosheets shorten the ion diffusion and electron transport paths and ensure the efficient penetration of electrolytes and full contact between electrolyte and electrode. The hierarchical design not only effectively retains the high energy density of the bulky material but also has the high specific capacity of the nanomaterials. As a result, the MoS₂@C@MoS₂ hierarchical material displays a high specific capacity of 1035 mAh g⁻¹ at 100 mA g⁻¹ after 200 cycles and 860 mAh g⁻¹ even at 1 A g⁻¹, demonstrating decent stable cycle life and rate performance. Additionally, the synthesis strategy of hierarchical materials proposed here offers a general route to design other bulky mineral materials.