Binder-Free Co₄N Nanoarray on Carbon Cloth as Flexible High-Performance Anode for Lithium-Ion Batteries

Abstract

The development of flexible energy storage devices is highly dependent on the exploration of flexible anode materials with high electrochemical performances. Therefore, growing active materials with large capacity on flexible substrate has been intensively investigated. We herein report a simple route for the fabrication of binder-free Co 4 N nanoarrays on carbon cloth (Co 4 N/ CC) as flexible and highly efficient anode of lithium-ion battery. High initial Coulombic efficiency can be achieved. The Co 4 N/CC exhibited a high capacity over 1100 mAh g −1 at 0.1 A g −1 and 855 mAh g −1 at 0.5 A g −1 , which both could be effectively retained at ∼90% after 150 and 300 cycles, respectively. At a high current density of 2.0 A g −1 , a high reversible capacity of 650 mAh g −1 was obtained. The excellent electrochemical performances can be primarily attributed to the high conductivity of Co 4 N and the unique architecture of Co 4 N/CC, in which needle-like Co 4 N nanoarrays fully cover the carbon fiber and serve as the antenna in the electrolyte, while CC works as electronic conductor. In addition, carbon fiber has been partially hybridized by nitrogen, which contributes to the extra lithium storage capability. Due to the relatively low voltage plateau of Co 4 N/CC, the full cell assembled with typical LiCoO 2 cathode showed a very favorable highvoltage (∼3.7 V) and high energy density and power density. Due to the simple and effective procedure, the current strategy can be readily extended for the fabrication of other transition-metal nitrides, holding a great promise for electrochemical applications.

Highly Lithiophilic Cobalt Nitride Nanobrush as a Stable Host for High-Performance Lithium Metal Anodes

“…It is well documented that the initial Li nucleation overpotential is closely associated with the lithiophilicity of the electrode surface. , As shown in Figure c, it is interesting to note that the Co 3 N/NF host exhibits a small lithiation plateau at around 170 mV, which is in association with the conversion reaction of Co 3 N accompanying by the formation of the Li 3 N phase. The Li 3 N phase could provide excellent Li + conductivity (∼10 –3 S cm –1 ) for the following Li deposition. , In addition, compared with metal oxide, metal nitride is an excellent electrically conductive material for electron transportation. As a result, the Co 3 N nanobrush is of high lithiophilicity to enable a low overpotential of 14.5 mV, which is lower than those of the bare NF (33.4 mV) and CoO (15.8 mV) substrates.…”

“…The Li 3 N phase could provide excellent Li + conductivity (∼10 −3 S cm −1 ) for the following Li deposition. 36,39 In addition, compared with metal oxide, metal nitride is an excellent electrically conductive material for electron transportation. As a result, the Co 3 N nanobrush is of high lithiophilicity to enable a low overpotential of 14.5 mV, which is lower than those of the bare NF (33.4 mV) and CoO (15.8 mV) substrates.…”

Expanding the interlamellar spacing of biomass-derived hybrids with intercalated nanotubes for enhanced oxygen reduction reaction

“…In this respect, Co@NC-CNT might exhibit better electron conductivity than Co@NC. 30,46 Besides, there are three minor peaks centered at 476 cm −1 , 516 cm −1 , and 678 cm −1 for Co@NC-CNT corresponding to the E g , F 2g , and A 1g vibrational modes of oxidized cobalt ion, 47,48 respectively, implying the interaction of cobalt with other atoms. Moreover, it should be noted that the peak intensity of Co@NC-CNT is much stronger than those of Co@NC.…”

Oxygen Vacancy Modulation of Bimetallic Oxynitride Anodes toward Advanced Li‐Ion Capacitors

“…The three electrodes exhibited two reduction peaks at 1.13 and 0.95 V, which might be ascribed to the structural transformation caused by lithium intercalation and further reduction to Co/Ni reaction, consistent with previous reports. [ 26 ] The lithiation of NiCoON mainly occurred at 0.88 V, whereas the reversible transition of NiCoON to Co/Ni and delithiation happened at 0.92 V. [ 27 ] Other peaks below 0.5 V appeared only in the CV curves of NiCoON and NiCoN materials, related to the CN functional group of the nitride carbon cloth. [ 28 ] At the same current density, the largest CV curve area of the NiCoON electrode indicated its superior energy storage performance and fast Li‐ion redox kinetics among the three samples.…”