Carbon-Anchored MnO Nanosheets as an Anode for High-Rate and Long-Life Lithium-Ion Batteries

Abstract

Developing electrode materials with high rate as well as prolonged cycle is particularly necessary for the ever-growing market penetration of electric vehicles and hybrid electric vehicle. Herein, we demonstrate a facile and efficient strategy to synthesize MnO/C hybrid via freeze-drying followed by thermal treatment in N2 atmosphere. The MnO nanosheets are firmly anchored onto carbon layers to form MnO/C hybrid. When used as an anode in lithium-ion batteries, the typical MnO/C hybrid displays a high initial Coulombic efficiency of 83.1% and delivers a high capacity of 1449.8 mAh g(-1) after 100 cycles at 0.3 A g(-1). Furthermore, the typical MnO/C hybrid can still maintain significantly high capacity of 1467.0 mAh g(-1) after 2000 cycles at 5 A g(-1), which may be the best performance reported so far for MnO-based materials. The superior electrochemical performance of the MnO/C hybrid may be attributed to its unique microstructure features such as effective conductive pathway of carbon sheets, firm connection between MnO and carbon sheets, and small-sized MnO.

Core‐shell MnO@MnFe2O4 Anchored by Reduced Graphene Oxide as Anode of Li‐Ion Batteries Operated under Ultrawide Temperature Range

“…As reported in references, the first discharge plateaus of MnO and Fe 2 O 3 were generally located at around 0.26 V (reduction of Mn 2 + to Mn) [14] and 0.68 V (reduction of Fe 3 + to Fe). Therefore, the broad reduction peaks at 0.32 V in CV profile of MnO@MnFe 2 O 4 @rGO at ambient temperature could be considered as the consequence of overlap of these peaks ( Figure S9a).…”

“…(1) the synthesis strategy may be proved to be cost‐effective and scalable, and artificially designed nanoparticles were allowed to avoid adverse size‐effects and potentially shape‐dependent kinetic and thermodynamic constraints for conversion reaction; (2) artificially designed core/shell structure provided an unique opportunity to integrate MnO and MnFe 2 O 4 into one whole particle with an ordered and controllable microstructure and particle size. In addition, core/shell structured nanocomposites may sprout additional lithium storage sites, leading to an outstanding performance such as enhanced reversible capacity;, and (3) enhanced kinetics at 60 °C has given rise to an excellent reversible capacity of 1067 mAh g −1 at a current density of 500 mA g −1 after 300 cycles…”

2D Film of Carbon Nanofibers Elastically Astricted MnO Microparticles: A Flexible Binder‐Free Anode for Highly Reversible Lithium Ion Storage

“…The main peak at 284.8 eV belongs to the sp 2hybridized graphite carbon. [15] Two weak peaks at 286.2 and 288.3 eV belong to CO and CO, respectively. [16] The N 1s core-level spectrum can be well fitted into a pyrodinic nitrogen (N-6) at 398.4 eV and a pyrrolic nitrogen (N-5) at 400.4 eV.…”

Effect of cobalt alloying on the electrochemical performance of manganese oxide nanoparticles nucleated on multiwalled carbon nanotubes

“…The MnO/Co structure exhibited improved reversible chargedischarge stability and it was concluded that deposition of the Co nanocrystals and the formation of a CoO surface layer were responsible for the enhanced performance. In addition, a significant number of previous reports on MnO-based materials show a dramatic increase in the capacity retention during cycling [13][14][15][16][17][18][19][20][21][22][23] which is most likely due to the formation of phases with higher oxidation states and correspondingly higher theoretical capacities (such as Mn 3 O 4 (936 mAhg −1 ), Mn 2 O 3 (1019 mAhg −1 ) [11], MnO 2 (1230 mAhg −1 ) [3]). However, in most cases even these materials exhibit poor high rate charge-discharge performance.…”