Metal Organic Frameworks Route to in Situ Insertion of Multiwalled Carbon Nanotubes in Co₃O₄ Polyhedra as Anode Materials for Lithium-Ion Batteries

Abstract

Hybridizing nanostructured metal oxides with multiwalled carbon nanotubes (MWCNTs) is highly desirable for the improvement of electrochemical performance of lithium-ion batteries. Here, a facile and scalable strategy to fabricate hierarchical porous MWCNTs/Co3O4 nanocomposites has been reported, with the help of a morphology-maintained annealing treatment of carbon nanotubes inserted metal organic frameworks (MOFs). The designed MWCNTs/Co3O4 integrates the high theoretical capacity of Co3O4 and excellent conductivity as well as strong mechanical/chemical stability of MWCNTs. When tested as anode materials for lithium-ion batteries, the nanocomposite displays a high reversible capacity of 813 mAh g(-1) at a current density of 100 mA g(-1) after 100 charge-discharge cycles. Even at 1000 mA g(-1), a stable capacity as high as 514 mAh g(-1) could be maintained. The improved reversible capacity, excellent cycling stability, and good rate capability of MWCNTs/Co3O4 can be attributed to the hierarchical porous structure and the synergistic effect between Co3O4 and MWCNTs. Furthermore, owing to this versatile strategy, binary metal oxides MWCNTs/ZnCo2O4 could also be synthesized as promising anode materials for advanced lithium-ion batteries.

General Synthesis of Porous Mixed Metal Oxide Hollow Spheres with Enhanced Supercapacitive Properties

“…Among them, cobalt oxides exhibit outstanding anodic performance. [1][2][3][4] Nevertheless they often suffer from high cost and toxicity, as well as poor conductivity. To solve these problems, much effort is being directed towards the fabrication of cheap and eco-friendly mixed metal oxides (MMOs) like ZnCo 2 MMO present higher electrochemical activity than their corresponding single metal oxides.…”

Hierarchical Tubular Structures Composed of Co3O4 Hollow Nanoparticles and Carbon Nanotubes for Lithium Storage

“…When al ower calcining temperature is applied in the oxidization step,s ignificant amount of residual carbon will remain in the final materials ( Figure S7 ba nd S12). [ 40] Them ain plateau at 2.1 Vc an be assigned to the delithiation of Co to Co 3 O 4 in the first charge process. [16] Thev oltage plateau obviously shifts to about 1.25 Vi nt he second discharge cycle,w hich could be mainly attributed to the structural variation of the electrode materials.…”

NiO hollow microspheres interconnected by carbon nanotubes as an anode for lithium ion batteries

“…However, the degree of its specific decay is less than that of NiO electrode. Notably, when at the rate 5C, the NiO/CNTs electrode shows 13 higher specific capacities than NiO. It retains 70.5% of initial capacity, much higher than pure NiO electrode of only 55.7%.…”

“…To further improve the rate performance of MOs, much effort has been made to accommodate the active materials with porous conductive scaffolds to form the nanocomposites such as carbon nanotubes [11][12][13][14][15][16][17][18][19], graphene [20][21][22][23][24] and carbon nanofibers [25][26][27][28][29] because they could provide long-range conductivity, well controlled interface between MOs and conducting carbons, and more robust network structure. In particular, CNTs is a good candidate for a support matrix in novel anode material for enhanced lithium storage due to its high electrical conductivity, rich porosity and high tensile strength [30,31].…”