Electrochemical Investigation of Natural Ore Molybdenite (MoS₂) as a First-Hand Anode for Lithium Storages

Considering serious pollution from the traditional chemical synthesis process, the resource-rich, clean, and first-hand electrode materials are greatly desired. Natural ore molybdenite (MoS₂), as the low-cost, high-yield, and environmental-friendly natural source, is investigated as a first-hand anode material for lithium-ion batteries (LIBs). Compared with chemosynthetic pure MoS₂, natural molybdenite provides an ordered ion diffusion channel more effectively owing to its excellent characteristics, containing well-crystalline, large lattice distance, and trance dopants. Even at a large current density of 2.0 A g^-1, a natural molybdenite electrode employing a carboxymethyl cellulose binder displays an initial charge capacity of 1199 mA h g^-1 with a capacity retention of 72% after 1000 cycles, much higher than those of the electrodes utilizing a poly(vinylidene fluoride) binder. These types of binders play a crucial role in stabilizing a microstructure demonstrated by ex situ scanning electron microscopy and in affecting pseudocapacitive contributions quantitatively determined by a series of kinetic exploration. Briefly, this work might open up a new avenue toward the use of natural molybdenite as a first-hand LIB anode in scalable applications and deepen our understanding on the fundamental effect of binders in the metal-sulfide.