Anthracite-Derived Porous Carbon@MoS₂ Heterostructure for Elevated Lithium Storage Regulated by the Middle TiO₂ Layer

The rational design of MoS₂/carbon composites have been widely used to improve the lithium storage capability. However, their deep applications remain a big challenge due to the slow electrochemical reaction kinetics of MoS₂ and weak bonding between MoS₂ and carbon substrates. In this work, anthracite-derived porous carbon (APC) is sequential coated by TiO₂ nanoparticles and MoS₂ nanosheets via a chemical activation and two-step hydrothermal method, forming the unique APC@TiO₂@MoS₂ ternary composite. The dynamic analysis, in-situ electrochemical impedance spectroscopy as well as theoretical calculation together demonstrate that this innovative design effectively improves the ion/electron transport behavior and alleviates the large volume expansion during cycles. Furthermore, the introduction of middle TiO₂ layer in the composite significantly strengthens the mechanical stability of the entire electrode. As expected, the as-prepared APC@TiO₂@MoS₂ anode displays a high lithium storage capacity with a reversible capacity of 655.8 mAh g^-1 after 150 cycles at 200 mA g^-1, and robust cycle stability. Impressively, even at a high current density of 2 A g^-1, the electrode maintains a superior reversible capacity of 597.7 mAh g^-1 after 1100 cycles. This design highlights a feasibility for the development of low-cost anthracite-derived porous carbon-based electrodes.