Boosting high-rate Li storage of bulb-like O-MoS2@C nanoreactors with sulfur vacancies and carbon

Molybdenum sulfide (MoS2) is a promising materials for lithium ion batteries, while the anodes often suffer from low capacity and poor endurability at high current conditions (?5 A g-1). Here, CTAB was employed as a soft template and carbon source to prepare monodispersed bulb-like O-MoS2@C nanoreactor for high-rate Li storage through an integrated approach. Specifically, bulb-like nanostructured MoS2 precursor were first prepared by microemulsion method. Rich sulfur vacancies were created along with the oxygen doping in anion exchange reaction. And amorphous carbon derived from CTAB is incorporated in the nanoreactor after annealing treatment. The resultant O-MoS2@C delivered average specific capacities of -1442 mA h g- 1 at 0.2 A g-1 and -394 mA h g-1 at 5 A g-1, and maintained reversible capacities of 1208 mA h g-1 after 200 cycles and -361 mA h g-1 after 700 cycles, respectively. Density functional theory (DFT) results indicated that the thermodynamic adsorption and kinetic migration of Li can become effortless through introducing carbon and vacancies. This work provides a controllable approach to produce nanoreactor with vacancies and in-situ carbon incorporated for high-rate and durable Li storage performances.

Automated summary

By incorporating CTAB and oxygen doping, along with the synthesis of bulb-like nanostructured MoS2 precursor, the O-MoS2@C nanoreactor was prepared. It delivered average specific capacities of -1442 mA h g-1 at 0.2 A g-1 and -394 mA h g-1 at 5 A g-1, maintaining reversible capacities of 1208 mA h g-1 after 200 cycles and -361 mA h g-1 after 700 cycles. Density functional theory results showed that the introduction of carbon and vacancies facilitated the thermodynamic adsorption and kinetic migration of Li, leading to high-rate and durable Li storage performances.