Limits...
Graphene wrapped ordered LiNi0.5Mn1.5O4 nanorods as promising cathode material for lithium-ion batteries.

Tang X, Jan SS, Qian Y, Xia H, Ni J, Savilov SV, Aldoshin SM - Sci Rep (2015)

Bottom Line: The morphological characterization by scanning electron microscopy and transmission electron microscopy reveals that the LiNi0.5Mn1.5O4 nanorods of 100-200 nm in diameter are well dispersed and wrapped in the graphene nanosheets for the composite.Benefiting from the highly conductive matrix provided by graphene nanosheets and one-dimensional nanostructure of the ordered spinel, the composite electrode exhibits superior rate capability and cycling stability.As a result, the LiNi0.5Mn1.5O4-graphene composite electrode delivers reversible capacities of 127.6 and 80.8 mAh g(-1) at 0.1 and 10 C, respectively, and shows 94% capacity retention after 200 cycles at 1 C, greatly outperforming the bare LiNi0.5Mn1.5O4 nanorod cathode.

View Article: PubMed Central - PubMed

Affiliation: 1] School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China [2] Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, Nanjing 210094, China.

ABSTRACT
LiNi0.5Mn1.5O4 nanorods wrapped with graphene nanosheets have been prepared and investigated as high energy and high power cathode material for lithium-ion batteries. The structural characterization by X-ray diffraction, Raman spectroscopy, and Fourier transform infrared spectroscopy indicates the LiNi0.5Mn1.5O4 nanorods prepared from β-MnO2 nanowires have ordered spinel structure with P4332 space group. The morphological characterization by scanning electron microscopy and transmission electron microscopy reveals that the LiNi0.5Mn1.5O4 nanorods of 100-200 nm in diameter are well dispersed and wrapped in the graphene nanosheets for the composite. Benefiting from the highly conductive matrix provided by graphene nanosheets and one-dimensional nanostructure of the ordered spinel, the composite electrode exhibits superior rate capability and cycling stability. As a result, the LiNi0.5Mn1.5O4-graphene composite electrode delivers reversible capacities of 127.6 and 80.8 mAh g(-1) at 0.1 and 10 C, respectively, and shows 94% capacity retention after 200 cycles at 1 C, greatly outperforming the bare LiNi0.5Mn1.5O4 nanorod cathode. The outstanding performance of the LiNi0.5Mn1.5O4-graphene composite makes it promising as cathode material for developing high energy and high power lithium-ion batteries.

No MeSH data available.


Related in: MedlinePlus

(a) Raman spectra of the pristine graphene nanosheets, the bare LiNi0.5Mn1.5O4 nanorods, and the LiNi0.5Mn1.5O4-graphene composite. (b) Enlargement of the Raman spectrum of the LiNi0.5Mn1.5O4 nanorods in the frequency range between 300 and 700 cm−1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493710&req=5

f3: (a) Raman spectra of the pristine graphene nanosheets, the bare LiNi0.5Mn1.5O4 nanorods, and the LiNi0.5Mn1.5O4-graphene composite. (b) Enlargement of the Raman spectrum of the LiNi0.5Mn1.5O4 nanorods in the frequency range between 300 and 700 cm−1.

Mentions: Raman spectra of the pristine graphene nanosheets, the bare LiNi0.5Mn1.5O4 nanorods, and the LiNi0.5Mn1.5O4-graphene composite are shown in Fig. 3a. The Raman spectra of the bare LiNi0.5Mn1.5O4 nanorods and the LiNi0.5Mn1.5O4-graphene composite show similar features in the frequency range of 300–1000 cm−1, which are in good agreement with published works on ordered LiNi0.5Mn1.5O4 spinel2324. The Raman spectrum of the LiNi0.5Mn1.5O4 nanorods in the frequency range between 300 to 700 cm−1 was enlarged and shown in Fig. 3b, revealing six Raman bands. The strong band around 638 cm−1 is assigned to the symmetric Mn-O stretching mode of MnO6 octahedral (A1g), while the two bands at 407 and 498 cm−1 are associated with the Ni2+-O stretching mode in the structure25. The peak near 580–620 cm−1 is considered as T2g(3) of the spinel compound, and the split of T2g(3) is the strong evidence of the ordered spinel due to its low symmetry (P4332). In the frequency range between 1000 and 3700 cm−1, the Raman spectrum of the LiNi0.5Mn1.5O4-graphene composite show similar Raman features as the pristine graphene nanosheets, revealing the characteristic D band, G band, and 2D band of graphene.


Graphene wrapped ordered LiNi0.5Mn1.5O4 nanorods as promising cathode material for lithium-ion batteries.

Tang X, Jan SS, Qian Y, Xia H, Ni J, Savilov SV, Aldoshin SM - Sci Rep (2015)

(a) Raman spectra of the pristine graphene nanosheets, the bare LiNi0.5Mn1.5O4 nanorods, and the LiNi0.5Mn1.5O4-graphene composite. (b) Enlargement of the Raman spectrum of the LiNi0.5Mn1.5O4 nanorods in the frequency range between 300 and 700 cm−1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493710&req=5

f3: (a) Raman spectra of the pristine graphene nanosheets, the bare LiNi0.5Mn1.5O4 nanorods, and the LiNi0.5Mn1.5O4-graphene composite. (b) Enlargement of the Raman spectrum of the LiNi0.5Mn1.5O4 nanorods in the frequency range between 300 and 700 cm−1.
Mentions: Raman spectra of the pristine graphene nanosheets, the bare LiNi0.5Mn1.5O4 nanorods, and the LiNi0.5Mn1.5O4-graphene composite are shown in Fig. 3a. The Raman spectra of the bare LiNi0.5Mn1.5O4 nanorods and the LiNi0.5Mn1.5O4-graphene composite show similar features in the frequency range of 300–1000 cm−1, which are in good agreement with published works on ordered LiNi0.5Mn1.5O4 spinel2324. The Raman spectrum of the LiNi0.5Mn1.5O4 nanorods in the frequency range between 300 to 700 cm−1 was enlarged and shown in Fig. 3b, revealing six Raman bands. The strong band around 638 cm−1 is assigned to the symmetric Mn-O stretching mode of MnO6 octahedral (A1g), while the two bands at 407 and 498 cm−1 are associated with the Ni2+-O stretching mode in the structure25. The peak near 580–620 cm−1 is considered as T2g(3) of the spinel compound, and the split of T2g(3) is the strong evidence of the ordered spinel due to its low symmetry (P4332). In the frequency range between 1000 and 3700 cm−1, the Raman spectrum of the LiNi0.5Mn1.5O4-graphene composite show similar Raman features as the pristine graphene nanosheets, revealing the characteristic D band, G band, and 2D band of graphene.

Bottom Line: The morphological characterization by scanning electron microscopy and transmission electron microscopy reveals that the LiNi0.5Mn1.5O4 nanorods of 100-200 nm in diameter are well dispersed and wrapped in the graphene nanosheets for the composite.Benefiting from the highly conductive matrix provided by graphene nanosheets and one-dimensional nanostructure of the ordered spinel, the composite electrode exhibits superior rate capability and cycling stability.As a result, the LiNi0.5Mn1.5O4-graphene composite electrode delivers reversible capacities of 127.6 and 80.8 mAh g(-1) at 0.1 and 10 C, respectively, and shows 94% capacity retention after 200 cycles at 1 C, greatly outperforming the bare LiNi0.5Mn1.5O4 nanorod cathode.

View Article: PubMed Central - PubMed

Affiliation: 1] School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China [2] Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, Nanjing 210094, China.

ABSTRACT
LiNi0.5Mn1.5O4 nanorods wrapped with graphene nanosheets have been prepared and investigated as high energy and high power cathode material for lithium-ion batteries. The structural characterization by X-ray diffraction, Raman spectroscopy, and Fourier transform infrared spectroscopy indicates the LiNi0.5Mn1.5O4 nanorods prepared from β-MnO2 nanowires have ordered spinel structure with P4332 space group. The morphological characterization by scanning electron microscopy and transmission electron microscopy reveals that the LiNi0.5Mn1.5O4 nanorods of 100-200 nm in diameter are well dispersed and wrapped in the graphene nanosheets for the composite. Benefiting from the highly conductive matrix provided by graphene nanosheets and one-dimensional nanostructure of the ordered spinel, the composite electrode exhibits superior rate capability and cycling stability. As a result, the LiNi0.5Mn1.5O4-graphene composite electrode delivers reversible capacities of 127.6 and 80.8 mAh g(-1) at 0.1 and 10 C, respectively, and shows 94% capacity retention after 200 cycles at 1 C, greatly outperforming the bare LiNi0.5Mn1.5O4 nanorod cathode. The outstanding performance of the LiNi0.5Mn1.5O4-graphene composite makes it promising as cathode material for developing high energy and high power lithium-ion batteries.

No MeSH data available.


Related in: MedlinePlus