3D Hierarchical Microballs Constructed by Intertwined MnO@N‐doped Carbon Nanofibers towards Superior Lithium‐Storage Properties

Abstract

MnO is a promising high-capacity anode material for lithium-ion batteries (LIBs), but pristine material suffers short cycle life and poor rate capability, thus hindering the practical application. In this work, a new type of porous MnO microballs stringed with N-doped porous carbon (3DHB-MnO@NC) with a well-connected hierarchical three-dimensional network structure was prepared by the facile self-template method. The 3DHB-MnO@NC electrode can effectively promote the ion/electron transfer and buffer the large volume change of electrode during the electrochemical reaction. As the anode for LIBs, the 3DHB-MnO@NC possesses outstanding cycling performance (1247.7 mA h g after 90 cycles at 200 mA g ) and good rate capabilities (949.6 mA h g after 450 cycles at 1000 mA g ). The facile self-template method of the prepared 3DHB-MnO@NC composite paves a new way for practical applications of MnO in high performance LIBs.

A Nitrogen‐Doped Manganese Oxide Nanoparticles/Porous Carbon Nanosheets Hybrid Material: A High‐Performance Anode for Lithium Ion Batteries

“…Above all, the reversible capacity of N−MnO/PCS‐1 electrode keeps increasing with cycling and finally reaches 1497.2 mA h g −1 after 160 cycles. The capacity increase phenomenon, which is also common in other transition metal oxides, could be related to the electrochemical activation of the porous structure, the production of polymeric gel‐like film derived from kinetically activated electrolyte degradation during the lithiation/de‐lithiation process and the formation defects caused by N‐doping treatment, as well as the production of higher oxidation state manganese, all these items possibly resulting in the improvement of the lithium storage of N−MnO/PCS‐1 electrode. For comparison, three other blank samples, such as MnO/PCS, N−PCS and N−Mn 2 O 3 electrodes, were also investigated at the same tested conditions, as shown in Figure c.…”

Highly Reversible Lithium Storage of Nitrogen‐Doped Carbon@MnO Hierarchical Hollow Spheres as Advanced Anode Materials

“…[8] XPS characterization of NC@MnO HHSs confirms that the C 1s spectrum can well fit to six peaks at 284.3, 284.8, 285.5, 286.5, 288.0 and 289.3 eV, which correspond to C=C, CÀ C, CÀ N, CÀ OH, C=O and OÀ C=O components, respectively ( Figure 4f). [9][10][11]14,38] N 2 ad-/desorption measurements reveal that the special surface area of NC@MnO HHSs is about 55.4 m 2 g À 1 , and their corresponding pore volume is 0.079 cm 3 g À 1 ( Figure S4).…”

“…0.25 V in the subsequent cycles, possibly caused by the gradual activation process of anode materials and the optimized kinetics after the initial insertion/extraction reaction. [8][9][10][11][12] The broad initial anodic peak of ca. 1.30 V can be assigned to evolution from Mn 0 to Mn 2 + (Mn + Li 2 O!MnO + 2Li + + 2e À ).…”

“…[1][2][3] However, to meet the increasing requirements for the ever-advancing power sources, the further development of high-performance and low-cost anode materials with novel nanostructures in LIBs is of significant importance. [4][5][6][7] Amongst metal oxides (MOs) as anode materials in LIBs, manganese monoxide (MnO) has attracted considerable attention because of its low cost, low working potential, [8,9] natural abundance, high theoretical capacity (756 mAh g À 1 ) and environmental benignity. [10,11] Unfortunately, the practical implementation of MnO-based anode materials is still obstructed because of their short cyclic life and unsatisfactory rate performance, attributable to their low conductivity, large volume variation and self-aggregation of MnO during intense cycles.…”

Synergic effects of the decoration of nickel oxide nanoparticles on silicon for enhanced electrochemical performance in LIBs

“…[1][2][3] Graphite is one of the important negative electrode materials in commercially available LIBs, but it is inadequate to full the energy demands in next-generation energy storage devices due to its low theoretical capacity. 4,5 Additionally, graphite has some safety issues because its operation potential is very close to that of lithium metal and it is very reactive toward certain electrolytes. 6,7 In commercial LIBs, silicon has been investigated as a promising anode material and a substitute for graphite anodes due to its high theoretical capacity of 4200 mA h g À1 with low operating potential, abundance and low cost.…”