Electrochemical characterization of Co3O4/MCNTs composite anode materials for sodium-ion batteries

Abstract

A composite of transition metal oxide Co 3 O 4 and multiwalled carbon nanotubes (MCNTs) was applied as an anode material for sodium-ion batteries via a simply modified solid-state reaction and sonication method. The as-prepared Co 3 O 4 /MCNTs composite shows improved electrochemical performance than bare Co 3 O 4 owing to the Co 3 O 4 /MCNTs nanostructure that benefits Na ion and electronic transport together with buffering the large volume change of Co 3 O 4 during charging and discharging process. Additionally, the Na-storage behavior and the original capacity loss of Co 3 O 4 based on the conversion reaction have been investigated through cyclic voltammogram, X-ray diffraction, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, and selected area electron diffraction. It is firstly demonstrated that in discharge state, Co 3 O 4 particles initially react with Na to produce CoO and then is further reduced to nanosized Co in an amorphous sodium oxides matrix. In the charge process, Co nanoparticles were partially oxidized to Co 3 O 4 , the other part of the CoO remain leading capacity loss. These results offer new insights into the electrochemical process of transition metal-based anode materials for Na-ion batteries.

Carbon‐Encapsulated Tube‐Wire Co3O4/MnO2 Heterostructure Nanofibers as Anode Material for Sodium‐Ion Batteries

“…Two characteristic peaks at 780.1 eV (Co 2p 3/2 ) and 795.1 eV (Co 2p 1/2 ) indicates that the binding energy of Co is in good agreement with value for Co 3 O 4 (Figure e) . The Mn 2p 3/2 and Mn 3p 1/2 are located at 642.1 and 653.8 eV, respectively, which corresponds to MnO 2 (Figure f) . The XPS results further confirm the existence of MnO 2 and Co 3 O 4 in the carbon‐encapsulated tube‐wire Co 3 O 4 /MnO 2 @C heterostructure nanofibers, which agrees with the XRD results.…”

Recent Progress in Electrode Materials for Sodium‐Ion Batteries

“…[ 398 ] Since then, several research groups have investigated cobalt oxides as potential anodes for NIBs and attempted to improve their electrochemical properties. [399][400][401][402][403][404] Recently, Yang et al proposed a highly ordered dual porosity mesoporous Co 3 O 4 as a stable anode for NIBs. [ 395 ] The ordered dual porosity mesoporous Co 3 O 4 anode can deliver a high specifi c capacity of ≈700 mA h g −1 during the initial discharge and ≈500 mA h g −1 upon extended cycles, which are much higher values than those (Figure 15 b).…”

The State and Challenges of Anode Materials Based on Conversion Reactions for Sodium Storage

“…Nevertheless, the conversion-type electrodes in SIBs exhibit fast capacity decay during cycling. [183][184][185] For example, bulk MoS 2 electrodes showed a discharge capacity of ≈940 mAh g −1 , but the capacity decreased to 148 mAh g −1 after 100 cycles. [185] Although multiple efforts have been devoted to identifying the origins of capacity loss and modifying the electrode structures, excellent capacity retention after hundreds of cycles has only been reported in a small number of cases.…”