A new method to prepare vanadium oxide nano-urchins as a cathode for lithium ion batteries

Abstract

Urchin-like vanadium oxide nanotube clusters, abbreviated to VO x -NUs, were synthesized using a new method. Vanadium pentoxide, having a layered structure, was modified by lithium fluoride (LiF) and transformed into bi-phase lithium vanadate as the inorganic precursor. Then, VO x -NUs were prepared by hydrothermal reaction with dodecylamine as a template. This is different from other molecular assembly methods reported. VO x -NUs-350 nano clusters were obtained by annealing VO x -NUs at a temperature of 350 C in air. Both samples were identified as three dimensional urchin-like nano clusters. Based on the characterization data obtained, a formation mechanism was established. By simply varying the LiF stoichiometric ratio, the nano tube density of the VO x -NUs could be controlled. VO x -NUs presented a higher initial rate capacity of 400 mA h g À1 and VO x -NUs-350 maintained a better capacity of 150 mA h g À1 after 50 cycles at a 100 mA g À1 current density between 1.5 and 4 V versus Li/Li + .

Facile Synthesis of V2O5 Hollow Spheres as Advanced Cathodes for High-Performance Lithium-Ion Batteries

“…Developing nanostructured materials has been demonstrated to be an effective method to address these critical issues because nanomaterials have a large surface area to provide more reaction sites and can effectively shorten the diffusion distance of lithium ions during the insertion/extraction, thereby resulting in an enhanced cycling performance and rate capability [ 15 , 16 ]. A variety of V 2 O 5 nanostructures, such as nanourchins [ 17 ], nanotubes [ 18 ], nanospikes [ 10 ], nanorods [ 8 ], nanowires [ 19 , 20 , 21 ], and nanobelts [ 22 , 23 , 24 , 25 ], have been fabricated, and improved electrochemical performance has been achieved with these materials when used as cathodes for LIBs. In particular, hollow structures are rather favorable because the unique hollow structure can effectively buffer the volume expansion of the V 2 O 5 cathode to improve the cycling performance [ 9 , 26 , 27 , 28 ].…”

The Electrochemical Stability of Starch Carbon as an Important Property in the Construction of a Lithium-Ion Cell

“…The lithium-ion diffusion is related to the phase angle in the low-frequency region. The smaller the phase angle is, the faster the lithium-ions’ diffusion is [ 43 ]. Thus, the graphene anode exhibits a more favorable diffusion angle (−32 to −55°) compared to CSC (−5 to −10°).…”

Synthesis and Morphological Control of VO2 Nanostructures via a One-Step Hydrothermal Method

“…However, low-dimensional nanomaterials might have the disadvantage of dispersibility (self-aggregation) due to their higher surface energy. Highly ordered three-dimensional (3D) vanadium oxide nanomaterials in the form of urchins [ 29 , 34 , 35 ], flowers [ 36 , 37 ] and tubes [ 29 , 31 , 32 ] have been synthesized to overcome this problem. Pan et al [ 34 ] presented the different morphologies of 3D vanadium oxide (VO x ) microstructures (urchin-like micro flowers, nanosheet-assembled microflowers, nanohorn-structure microspheres) that were synthesized using a VOC 2 O 4 precursor using the solvothermal synthesis method.…”