Facile and Controllable Synthesis of Co₂V₂O₇ Microplatelets Anchored on Graphene Layers toward Superior Li-Ion Battery Anodes

Abstract

Co 2 V 2 O 7 /graphene composites were synthesized for lithium-ion battery (LIBs) anodes in a facile water-bath approach. The hexagonal Co 2 V 2 O 7 microplatelets attached uniformly to the few-layer graphene. As an unique hybrid architecture, Co 2 V 2 O 7 /graphene composites displayed an outstanding reversible capacity of 1048 mA h g −1 at a current density of 1 A g −1 over 300 cycles. The composite also demonstrated superior rate capability (∼600 mA h g −1 at 2 A g −1 ) because of the suppression of volume expansion and the improved electrical conductivity by graphene, which was corroborated by the theoretical calculations using the density function theory. Because of the synergistic effects of graphene and Co 2 V 2 O 7 , the composite exhibited substantial potential as a next-generation anode material for LIBs.

Rational Synthesis of “Grape‐like” Ni2V2O7 Microspheres as High‐capacity Anodes for Rechargeable Lithium Batteries

“…It should be pointed out that though ex‐situ XRD patterns were not available at this point, it is conjectured the reversible capacity is majorly relying on conversion‐type reaction (NiO−Ni) and intercalation‐type reaction (Li x V 2 O 5 −Li x+y V 2 O 5 ). The CV curves are similar to those of Ni 3 V 2 O 8 , Co 3 V 2 O 8 and Co 2 V 2 O 7 , implying similar electrochemical reaction mechanism [26,27,41–45] . Besides, the CV curves of V 2 O 5 /Ni 2 V 2 O 7 are shown in Figure S7 and Figure S8.…”

“…The CV curves are similar to those of Ni 3 V 2 O 8 , Co 3 V 2 O 8 and Co 2 V 2 O 7 , implying similar electrochemical reaction mechanism. [26,27,[41][42][43][44][45] Besides, the CV curves of V 2 O 5 /Ni 2 V 2 O 7 are shown in Figure S7 and Figure S8. In the first cathodic scan, there is obvious peak around 1.7 V in support of the insertion of Li-ions into V 2 O 5 .…”

Challenges and Design Strategies for Conversion-Based Anode Materials for Lithium- and Sodium-Ion Batteries

“…However, distinguishing SEI and PGF remains unclear because the components are similar in both cases, and there are controversial arguments about decomposable components [40,41,59,60]. As the components of the surface layer such as lithium/ sodium carbonate, fluoride, alkyl carbonate, and hydrocarbons are decomposition products of the electrolyte, the term electrolyte-derived surface layer is used [46,[61][62][63] along with the PGF and SEI.…”

Lithium‐ion battery anode with high capacity retention derived from zinc vanadate and holey graphene

“…initially emerged as promising materials as a cathode material in batteries including SIBs, LIBs, ZIBs and KIBs but have recently gained attention as anodes, especially their carbon-based composites have proven their flair as a robust anode material in many of this battery chemistries. 13,14 M 3 V 2 O 7 21 and M 3 V 2 O 8 . 22,23 The very known limiting factors include low electronic and ionic conductivity, besides the undesired volume expansion that bothers more capacity degradation, particularly at increased current densities.…”