3 research outputs found
Layer-by-Layer Polyelectrolyte Assisted Growth of 2D Ultrathin MoS<sub>2</sub> 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 MoS<sub>2</sub> 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 MoS<sub>2</sub> nanosheets on
these 1D carbons irrespective of their surface properties. Such unique
structures of the as-prepared CNTs@MoS<sub>2</sub> 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@MoS<sub>2</sub> hybrids exhibit excellent electrochemical
performances for lithium storage, including a high reversible capacity
(1027 mAh g<sup>–1</sup>), high-rate capability (610 mAh g<sup>–1</sup> at 5 C), and excellent cycling stability (negligible
capacity loss after 200 continuous cycles)
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<sup>–1</sup> at 46.2 mA g<sup>–1</sup> current density. Even at a high current density of
46.2 A g<sup>–1</sup>, the electrode still delivers
a capacity of 570.8 mAh g<sup>–1</sup>. When cycled
at 2.31 A g<sup>–1</sup>, 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
Low-Cost Synthesis of Hierarchical V<sub>2</sub>O<sub>5</sub> Microspheres as High-Performance Cathode for Lithium-Ion Batteries
Hierarchical V<sub>2</sub>O<sub>5</sub> 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, V<sub>2</sub>O<sub>5</sub> microspheres manifest a high
capacity (266 mA h g<sup>–1</sup>), excellent rate capability
(223 mA h g<sup>–1</sup> at a current density 2400 mA g<sup>–1</sup>), and good cycling stability (200 mA h g<sup>–1</sup> after 100 cycles) as cathode materials for lithium-ion batteries