Layer-by-Layer Polyelectrolyte Assisted Growth of 2D Ultrathin MoS₂ Nanosheets on Various 1D Carbons for Superior Li-Storage

Transitional metal sulfide/carbon hybrids with well-defined structures could not only maximize the functional properties of each constituent but engender some unique synergistic effects, holding great promise for applications in Li-ion batteries and supercapacitors and for catalysis. Herein, a facile and versatile approach is developed to controllably grow 2D ultrathin MoS₂ nanosheets with a large quantity of exposed edges onto various 1D carbons, including carbon nanotubes (CNTs), electrospun carbon nanofibers, and Te-nanowire-templated carbon nanofibers. The typical approach involves the employment of layer-by-layer (LBL) self-assembled polyelectrolyte, which controls spatially the uniform growth and orientation of ultrathin MoS₂ nanosheets on these 1D carbons irrespective of their surface properties. Such unique structures of the as-prepared CNTs@MoS₂ hybrid are significantly favorable for the fast diffusions of both Li-ions and electrons, satisfying the kinetic requirements of high-power lithium ion batteries. As a result, CNTs@MoS₂ hybrids exhibit excellent electrochemical performances for lithium storage, including a high reversible capacity (1027 mAh g^–1), high-rate capability (610 mAh g^–1 at 5 C), and excellent cycling stability (negligible capacity loss after 200 continuous cycles)

Low-Cost Synthesis of Hierarchical V₂O₅ Microspheres as High-Performance Cathode for Lithium-Ion Batteries

Hierarchical V₂O₅ microspheres composed of stacked platelets are fabricated through a facile, low-cost, and energy-saving approach. The preparation procedure involves a room-temperature precipitation of precursor microspheres in aqueous solution and subsequent calcination. Because of this unique structure, V₂O₅ microspheres manifest a high capacity (266 mA h g^–1), excellent rate capability (223 mA h g^–1 at a current density 2400 mA g^–1), and good cycling stability (200 mA h g^–1 after 100 cycles) as cathode materials for lithium-ion batteries

Ultrahigh-Capacity Organic Anode with High-Rate Capability and Long Cycle Life for Lithium-Ion Batteries

Organic rechargeable batteries have attracted extensive attention as a potential alternative for the current lithium-ion batteries. However, most of the reports are limited to organic macromolecules or modified small organic molecules which exhibit low reversible capacity, poor rate capability, and very limited cycle life. Herein, a small organic compound, maleic acid, is adopted as the anode for lithium ion batteries without any modification. It exhibits an ultrahigh reversible capacity of ca. 1500 mAh g^–1 at 46.2 mA g^–1 current density. Even at a high current density of 46.2 A g^–1, the electrode still delivers a capacity of 570.8 mAh g^–1. When cycled at 2.31 A g^–1, a capacity retention of 98.1% is obtained after 500 cycles. The excellent performance of the maleic acid organic anode is ascribed to its small volume effect and unique lithium-ion storage mechanisms. This new type of organic anode material may have a great opportunity for large-scale energy-storage systems with high-power properties