Metal Oxide Wrapped by Reduced Graphene Oxide Nanocomposites as Anode Materials for Lithium-Ion Batteries

Abstract

The reduced graphene oxide/iron oxide (rGO/Fe2O3) and reduced graphene oxide/cobalt oxide (rGO/Co3O4) composite anodes have been successfully prepared through a simple and scalable ball-milling synthesis. The substantial interaction of Fe2O3 and Co3O4 with the rGO matrix strengthens the electronic conductivity and limits the volume variation during cycling in the rGO/Fe2O3 and rGO/Co3O4 composites because reduced graphene oxide (rGO) helps the metal oxides (MOs) to attain a more efficient diffusion of Li-ions and leads to high specific capacities. As anode materials for LIBs, the rGO/Fe2O3 and rGO/Co3O4 composites demonstrate overall superb electrochemical properties, especially rGO/Fe2O3T−5 and rGO/Co3O4T−5, showcasing higher reversible capacities of 1021 and 773 mAhg−1 after 100 cycles at 100 mAg−1, accompanied by the significant rate performance. Because of their superior electrochemical efficiency, high capacity and low cost, the rGO/Fe2O3 and rGO/Co3O4 composites made by ball milling could be outstanding anode materials for LIBs. Due to the excellent electrochemical performance, the rGO/Fe2O3 and rGO/Co3O4 composites prepared via ball milling could be promising anode materials with a high capacity and low cost for LIBs. The findings may provide shed some light on how other metal oxides wrapped by rGO can be prepared for future applications.

Preparation of Nitrogen‐Doped Graphene with Hollow Nano‐Hemispheres from FexOy@Fe‐N‐GN: Towards High Capacity and Durable Anode for Li‐Ion Batteries by Chemical Modifications

“…The equivalent circuit elements for each sample are given in Figure S6. Notably, the overall resistances observed below 50 Ω up to the 100 th cycle are remarkably lower than many carbon‐coated metal oxide anodes in the literature due to the graphene‐containing structures in all samples [15,16,35] . The bulk resistance ( R S ) exhibited a gradual increase, while R SEI decreased up to the 100 th cycle, consistent with the stable SEI formation seen in CVs, and then increased along with the aging for all samples.…”

“…Notably, the overall resistances observed below 50 Ω up to the 100 th cycle are remarkably lower than many carbon-coated metal oxide anodes in the literature due to the graphene-containing structures in all samples. [15,16,35] The bulk resistance (R S ) exhibited a gradual increase, while R SEI decreased up to the 100 th cycle, consistent with the stable SEI formation seen in CVs, and then increased along with the aging for all samples. As expected, for Fe x O y @Fe-N-GN, an excessive increase in charge transfer resistance (R CT ) was observed due to distortions in Fe x O y structures caused by the volumetric change of Fe x O y in each lithiation/delithiation cycle.…”

“…[14] Hence, the capacity and cycling performances of fabricated metal oxide/graphene composites as anodes for lithium-ion batteries were investigated. [15] Wu et al prepared different hollow and solid bimetal oxide-graphene composite electrodes and found that CoFe 2 O/RGO composite exhibits excellent rate capability and high-rate cycling stability for lithium storage due to their stable, rigid structure. [16] In addition to combining the properties of graphene with transition metal oxides, the doping of graphene with heteroatoms such as nitrogen, boron, and sulfur could modulate the electrochemical properties of graphene, leading to the formation of new highcapacity active sites for lithium-ion storage.…”

“…Graphene as a support material for metal oxide nanoparticles not only improves the anode performance by improving the electronic and mechanical properties but also leads to new physical and electrochemical properties arising due to the synergistic effect that graphene or metal oxide alone cannot exhibit [14] . Hence, the capacity and cycling performances of fabricated metal oxide/graphene composites as anodes for lithium‐ion batteries were investigated [15] . Wu et al.…”

Ultrathin nanosheet-decorated honeycomb-like Co3O4 porous balls for high performance lithium-ion batteries

“…These factors contribute to electrode pulverization and ultimately lead to poor electrochemical performance. 5 These limitations hinder the ability of Co 3 O 4 to be readily utilized as an anode electrode material for LIBs in practical applications.…”