Cobalt Oxide-Carbon Nanosheet Nanoarchitecture as an Anode for High-Performance Lithium-Ion Battery

Abstract

To improve the electrochemical performance of cobalt oxide owing to its inherent poor electrical conductivity and large volume expansion/contraction, Co3O4-carbon nanosheet hybrid nanoarchitectures were synthesized by a facile and scalable chemical process. However, it is still a challenge to control the size of Co3O4 particles down to ∼5 nm. Herein, we created nanosized cobalt oxide anchored 3D arrays of carbon nanosheets by the control of calcination condition. The uniformly dispersed Co3O4 nanocrystals on carbon nanosheets held a diameter down to ∼5 nm. When tested as anode materials for lithium-ion batteries, high lithium storage over 1200 mAh g(-1) is achieved, whereas high rate capability with capacity of about 390 mAh g(-1) at 10 A g(-1) is maintained through nanoscale diffusion distances and interconnected porous structure. After 500 cycles, the cobalt oxide-carbon nansheets hybrid display a reversible capacity of about 970 mAh g(-1) at 1 A g(-1). The synergistic effect between nanosized cobalt oxide and sheetlike interconnected carbon nanosheets lead to the greatly improved specific capacity and the initial Coulombic efficiency of the hybrids.

Cobalt oxide nanosheets anchored onto nitrogen-doped carbon nanotubes as dual purpose electrodes for lithium-ion batteries and oxygen evolution reaction

“…When the current density restores to 0.2 A g −1 , the Ni foam‐supported Co 3 O 4 nanosheets receive the highest capacity of ~1600 mAh g −1 . The much higher specific capacity of Co 3 O 4 than its theoretical value in the as‐prepared electrodes may be due to the reversible growth of pseudocapacitive polymeric film and abundant active sites/defects for extra Li + adsorption/desorption . By contrast, the substrate of the Ni foam‐supported N‐CNTs exhibits stable discharge capacities at each current density.…”

“…Furthermore, the bare Co 3 O 4 nanoparticles could only remain ~7.1% of its initial capacity at 500 mA g −1 . In efforts to tackle the drawbacks of Co 3 O 4 , one general route is to fabricate Co 3 O 4 into various nanostructures with conducting substrates (eg, various carbon materials) . For instance, Wu et al reported that the graphene‐anchored Co 3 O 4 nanoparticles demonstrated superior electrochemical performance in LIBs, accounting for higher reversible capacity, longer cyclic life, and better rate capability over the bare Co 3 O 4 nanoparticles .…”

3D Metal‐Rich Cu7.2S4/Carbon‐Supported MoS2 Nanosheets for Enhanced Lithium‐Storage Performance

“…Consistent with the above SEM observations, the TEM images clearly revealed the core-shell structure of the Cu 7.2 S 4 /C@MoS 2 nanocomposite. [42,47] The electrochemical performance of pristine MoS 2 nanosheets, Cu 7.2 S 4 /C nanocomposite and 3D core-shell Cu 7.2 S 4 / C@MoS 2 nanocomposite as anode for LIBs were investigated, which were assembled into coin cells and tested under the identical electrochemical condition. 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 Nitrogen adsorption-desorption measurements were performed to study the differences between the specific surface area and pore-size distribution for the obtained samples.…”

“…The average pore size of 3D core-shell Cu 7.2 S 4 /C@MoS 2 nanocomposite was about 12.6 nm according to the Barrett-Joyner-Halenda (BJH) curves (Figure 4), while the special porous structure would bring about rapid electrolyte diffusion and accommodate volume expansion during electrochemical reactions to a certain extent. [42,47] The electrochemical performance of pristine MoS 2 nanosheets, Cu 7.2 S 4 /C nanocomposite and 3D core-shell Cu 7.2 S 4 / C@MoS 2 nanocomposite as anode for LIBs were investigated, which were assembled into coin cells and tested under the identical electrochemical condition. Figure 5a and 5b showed the cyclic voltammograms (CV) curves of 3D core-shell Cu 7.2 S 4 / C@MoS 2 nanocomposite and pristine MoS 2 nanosheets electrodes for the initial four cycles, and CV curves for the first four cycles of Cu 7.2 S 4 /C nanocomposite were displayed in Figure S3, which revealed the Li + intercalation/deintercalation mechanism of the electrode material.…”

Rational synthesis of Ni nanoparticle-embedded porous graphitic carbon nanosheets with enhanced lithium storage properties

“…The discharge and charge capacities of the first cycle are 1616 and 847 mAhg -1 , respectively, leading to an initial Coulombic efficiency (CE) of 52.4%. The initial capacity loss occurred in the first cycle is mostly caused by some irreversible side reactions such as the formation of the SEI layer as well as the decomposition of electrolyte in such carbon nanosheets with a high surface area 37,38. A discharge capacity of 896 mAg -1 is delivered in the third cycle, followed by a charge capacity of 839 mAg (a) Representative CVs of the 2D Ni@PGC nanosheets at a scan rate of 0.Charge-discharge voltage profiles of the 2D Ni@PGC nanosheets at a current density of 100 mAg −1 .…”