A series of nanostructured carbon/antimony composites have been successfully synthesized by a simple sol-gel, high-temperature carbon thermal reduction process. In the carbon/antimony composites, antimony nanoparticles are homogeneously dispersed in the pyrolyzed nanoporous carbon matrix. As an anode material for lithium-ion batteries, the C/Sb10 composite displays a high initial discharge capacity of 1214.6 mAh g(-1) and a reversible charge capacity of 595.5 mAh g(-1) with a corresponding coulombic efficiency of 49 % in the first cycle. In addition, it exhibits a high reversible discharge capacity of 466.2 mAh g(-1) at a current density of 100 mA g(-1) after 200 cycles and a high rate discharge capacity of 354.4 mAh g(-1) at a current density of 1000 mA g(-1) . The excellent cycling stability and rate discharge performance of the C/Sb10 composite could be due to the uniform dispersion of antimony nanoparticles in the porous carbon matrix, which can buffer the volume expansion and maintain the integrity of the electrode during the charge-discharge cycles.
Herein, we propose a strategy to prepare Ni/MoO2 microflowers (Ni/MoO2/C) for lithium‐ion batteries through a facile aqueous phase reaction at room temperature. NiMoO4 nanowires, as the Ni and Mo source, can chelate with dopamine to form a hierarchical microflower structure. The nickel content and the structure have significant influence on the performance for the final product. In the electrochemical measurements, the Ni/MoO2/C electrode reveals a high initial discharge capacity of 1117.3 mA h g−1 and a high capacity retention of 693.3 mA h g−1 after 100 cycles after an activated process at 1 A g−1. Meanwhile, an excellent rate capability from 0.1 A to 5 A g−1, where the discharge capacity is 1374 to 406 mA h g−1, is obtained. The high capability suggests that Ni/MoO2/C may be a promising candidate as an anode material for lithium‐ion batteries.
While vanadium oxides have garnered interest due to their
high
capacity and abundant valence states in aqueous zinc-ion batteries
(AZIBs), there are many challenges to achieving long cycling stability
and excellent rate capability resulting from poor electronic conductivity
and sluggish reaction dynamics. Herein, we design a cathode material
VN
x
O
y
/C derived
from a self-assembled V-polydopamine complex via a one-step organic–inorganic
hybrid reaction. Benefiting from a well-organized structure and nanosized
particle embedding, the as-prepared VN
x
O
y
phase could favor zinc-ion insertion/extraction
due to the strong affinity of N element with Zn2+. Systematic
investigations show that the controllable strategy yields positive
effects on the electrochemical performances including enhanced rate
capability and cycling stability, which are superior to those of the
V2O3/C cathode. As a result, we have achieved
fast charging/discharging capability at 10 A g–1 and stability exceeding 700 cycles at 3 A g–1 with
nearly 100% Coulombic efficiency. Interestingly, the pouch-cell-like
devices with ∼24 mAh could light an LED effectively. This work
may pave the way to obtaining highly active V-containing compounds
with structure design to improve electrochemical performances of AZIBs.
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