Cobalt‐based metal organic framework ( Co‐MOFs )/graphene oxide composites as high‐performance anode active materials for lithium‐ion batteries

Abstract

Summary Conventional graphene oxide cannot be directly used as an anode active material for lithium‐ion batteries owing to its surface state and lithium‐ion steric hindrance effect. To solve these problems, Co‐MOFs/graphene oxide composite active materials are synthesized by a facile solvothermal method. Through X‐ray diffraction and Raman spectrum analysis, Co‐MOFs and graphene oxide can interact with each other in the composite material and the structure, defect concentrations and graphitization degree of graphene oxide have been affected to a certain impact. Scanning electron microscopy observes that when the mass ratio of Co‐MOFs and graphene oxide is 1:1, this composite material shows more ideal and ordinal layered morphology. As anode active materials, they display electrochemical reaction characteristics of typical soft carbon and create abundant active sites with wide energy distribution and ameliorate the steric effect of graphene oxide on lithium ion. It also can be illustrated that the initial discharge specific capacities can achieve to 873.13, 795.41, 694.91 and 569.50 mAh·g−1 at 100, 200, 300 and 500 mA·g−1 current densities. After 500 cycles, capacity retention rates are 79.28%, 76.82%, 87.35% and 96.82% at 100, 200, 500 and 1000 mA·g−1 current densities. Electrochemical mechanism analysis shows that this Co‐MOFs/graphene oxide composite active material shows a similar electrochemical reaction process of graphene oxide and Co‐MOFs mainly play the role of optimizing the surface structure of graphene oxide and also supply a little capacity due to high specific capacity. Highlights Co‐MOFs/graphene oxide composites are synthesized by a facile solvothermal method. Co‐MOFs mainly play the role of optimizing the surface structure of graphene oxide. Anode using this composite material has a very high initial discharge specific capacity. This composite active material can stably charge and discharge for 500 cycles.

Review—Recent Advancements in Graphene-Based Electrodes for Lithium-Ion Batteries

“…In addition, graphenebased composites have emerged as an important path for developing anode-active materials in LIBs, with numerous promising outcomes. 54,55 Because of their potential to improve the battery's cycle performance, silicon-based nanocomposites based on graphene have garnered significant attention in academic research as potential for LIBs as anode materials since 2010. 56 There has been a lot of research into using it because of its large theoretical capacity, and silicon is used as an anode material in high-energy density lithiumion batteries of 4200 mAh g −1 and its abundance in nature.…”

A comprehensive review of various carbonaceous materials for anodes in lithium-ion batteries

“…138 The hydrothermal or solvothermal reactions are easy to perform and take advantage of the favourable synergistic effects of graphene with other elements, resulting in materials with higher electrical conductivity, high reversible capacity and extremely limited volume expansion compared to any monomer material. Lang et al 139 synthesized Co-MOFs/graphene oxide composite active materials (Co-MOFs/GO) by conventional Hummers and simple solvothermal methods. Co-MOFs and graphene oxide interact with each other in the composites, which have a specific influence on the structure, defect concentration, and graphitization degree of graphene oxide, showing a more ideal and ordered layer morphology.…”

“…10 (a) Cycle curves of Co-MOFs/GO with different proportions. 139 (b) Long-term cycle performance of GTO at 1 A g −1 for 300 cycles. 140 (c) 3D structure of NiO@graphene.…”

Exploring the Optical and Energetic Properties of a Co(II)-Based Mixed Ligand MOF

“…Owing to their good chemical stability, significant surface area, and ultrahigh porosity, they benefit from the assemblage of metal clusters and organic ligands, making them an ideal electrode candidate. Additionally, porous MOF materials exhibit several benefits when exploited as electrodes in lithium-based batteries: − (i) their porous structure allows for the penetration of electrolytes; (ii) their tunable surface and structure are exploited to optimize their performance; and (iii) their highly flexible components ensure the incorporation of electro-active sites. − In 2006, Li and colleagues investigated the first Zn-MIL-177- MOF anode materials with the general formula Zn 4 O­(C 9 H 6 O 6 ) 2 for rechargeable lithium-ion batteries. However, due to its poor cycling stability, the electrochemical performance of MOF-177 for Li-ion storage was insufficient.…”