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Hierarchical Core/Shell NiCo2O4@NiCo2O4 Nanocactus Arrays with Dual-functionalities for High Performance Supercapacitors and Li-ion Batteries.

Cheng J, Lu Y, Qiu K, Yan H, Xu J, Han L, Liu X, Luo J, Kim JK, Luo Y - Sci Rep (2015)

Bottom Line: As the SC electrode, they deliver a remarkable specific capacitance of 1264 F g(-1) at a current density of 2 A g(-1) and ~93.4% of capacitance retention after 5000 cycles at 2 A g(-1).When used as the anode for LIBs, a high reversible capacity of 925 mA h g(-1) is achieved at a rate of 120 mA g(-1) with excellent cyclic stability and rate capability.The ameliorating features of the NiCo2O4 core/shell structure grown directly on highly conductive Ni foam, such as hierarchical mesopores, numerous hairy needles and a large surface area, are responsible for the fast electron/ion transfer and large active sites which commonly contribute to the excellent electrochemical performance of both the SC and LIB electrodes.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Advanced Micro/Nano Functional Materials, School of Physics and Electronic Engineering, Xinyang Normal University, Xinyang, P. R. China.

ABSTRACT
We report the synthesis of three dimensional (3D) NiCo2O4@NiCo2O4 nanocactus arrays grown directly on a Ni current collector using a facile solution method followed by electrodeposition. They possess a unique 3D hierarchical core-shell structure with large surface area and dual-functionalities that can serve as electrodes for both supercapacitors (SCs) and lithium-ion batteries (LIBs). As the SC electrode, they deliver a remarkable specific capacitance of 1264 F g(-1) at a current density of 2 A g(-1) and ~93.4% of capacitance retention after 5000 cycles at 2 A g(-1). When used as the anode for LIBs, a high reversible capacity of 925 mA h g(-1) is achieved at a rate of 120 mA g(-1) with excellent cyclic stability and rate capability. The ameliorating features of the NiCo2O4 core/shell structure grown directly on highly conductive Ni foam, such as hierarchical mesopores, numerous hairy needles and a large surface area, are responsible for the fast electron/ion transfer and large active sites which commonly contribute to the excellent electrochemical performance of both the SC and LIB electrodes.

No MeSH data available.


Related in: MedlinePlus

XRD patterns of NiCo2O4@NiCo2O4 and NiCo2O4 NCAs.
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f2: XRD patterns of NiCo2O4@NiCo2O4 and NiCo2O4 NCAs.

Mentions: The crystallographic phase of the NiCo2O4@NiCo2O4 NCAs was identified by XRD, and the typical wide-angle diffraction patterns were shown in Fig. 2. They consisted of seven well-defined diffraction peaks that can be indexed into a cubic spinel NiCo2O4 crystalline structure (JCPDF card No. 20-0781). In general, the coexistence of Co and Ni in the oxide favors the formation of NiCo2O423. The composition and structure of the NiCo2O4@NiCo2O4 NCAs were further confirmed by Raman analysis, as shown in Figure S1. Four prominent peaks were observed at 187, 477.8, 523.5 and 671.2 cm−1, assigning to the F2g, Eg, F2g and A1g models of NiCo2O4, respectively. Only the Co-O and Ni-O vibrations were detected, indicating that the precursor cobalt/nickel carbonate hydroxide salts were completely transformed into oxides after calcinating at 350 oC. These results are consistent with those reported previously2425.


Hierarchical Core/Shell NiCo2O4@NiCo2O4 Nanocactus Arrays with Dual-functionalities for High Performance Supercapacitors and Li-ion Batteries.

Cheng J, Lu Y, Qiu K, Yan H, Xu J, Han L, Liu X, Luo J, Kim JK, Luo Y - Sci Rep (2015)

XRD patterns of NiCo2O4@NiCo2O4 and NiCo2O4 NCAs.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4487229&req=5

f2: XRD patterns of NiCo2O4@NiCo2O4 and NiCo2O4 NCAs.
Mentions: The crystallographic phase of the NiCo2O4@NiCo2O4 NCAs was identified by XRD, and the typical wide-angle diffraction patterns were shown in Fig. 2. They consisted of seven well-defined diffraction peaks that can be indexed into a cubic spinel NiCo2O4 crystalline structure (JCPDF card No. 20-0781). In general, the coexistence of Co and Ni in the oxide favors the formation of NiCo2O423. The composition and structure of the NiCo2O4@NiCo2O4 NCAs were further confirmed by Raman analysis, as shown in Figure S1. Four prominent peaks were observed at 187, 477.8, 523.5 and 671.2 cm−1, assigning to the F2g, Eg, F2g and A1g models of NiCo2O4, respectively. Only the Co-O and Ni-O vibrations were detected, indicating that the precursor cobalt/nickel carbonate hydroxide salts were completely transformed into oxides after calcinating at 350 oC. These results are consistent with those reported previously2425.

Bottom Line: As the SC electrode, they deliver a remarkable specific capacitance of 1264 F g(-1) at a current density of 2 A g(-1) and ~93.4% of capacitance retention after 5000 cycles at 2 A g(-1).When used as the anode for LIBs, a high reversible capacity of 925 mA h g(-1) is achieved at a rate of 120 mA g(-1) with excellent cyclic stability and rate capability.The ameliorating features of the NiCo2O4 core/shell structure grown directly on highly conductive Ni foam, such as hierarchical mesopores, numerous hairy needles and a large surface area, are responsible for the fast electron/ion transfer and large active sites which commonly contribute to the excellent electrochemical performance of both the SC and LIB electrodes.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Advanced Micro/Nano Functional Materials, School of Physics and Electronic Engineering, Xinyang Normal University, Xinyang, P. R. China.

ABSTRACT
We report the synthesis of three dimensional (3D) NiCo2O4@NiCo2O4 nanocactus arrays grown directly on a Ni current collector using a facile solution method followed by electrodeposition. They possess a unique 3D hierarchical core-shell structure with large surface area and dual-functionalities that can serve as electrodes for both supercapacitors (SCs) and lithium-ion batteries (LIBs). As the SC electrode, they deliver a remarkable specific capacitance of 1264 F g(-1) at a current density of 2 A g(-1) and ~93.4% of capacitance retention after 5000 cycles at 2 A g(-1). When used as the anode for LIBs, a high reversible capacity of 925 mA h g(-1) is achieved at a rate of 120 mA g(-1) with excellent cyclic stability and rate capability. The ameliorating features of the NiCo2O4 core/shell structure grown directly on highly conductive Ni foam, such as hierarchical mesopores, numerous hairy needles and a large surface area, are responsible for the fast electron/ion transfer and large active sites which commonly contribute to the excellent electrochemical performance of both the SC and LIB electrodes.

No MeSH data available.


Related in: MedlinePlus