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Hydrothermally Processed Oxide Nanostructures and Their Lithium-ion Storage Properties.

Ahn JH, Kim YJ, Wang G - Nanoscale Res Lett (2010)

Bottom Line: Y- and Si-based oxide nanopowders were synthesized by a hydrothermal reaction of Y or Si powders with NaOH or LiOH aqueous solution.The preliminary result of electrochemical examination showed that the hydrothermally processed nanowires exhibit high initial capacities of Li-ion storage: 653 mAh/g for Y(2)O(3) nanowires as anode materials and 186 mAh/g for Li(2)Si(2)O(5) nanowires as cathode materials in a Li secondary cell.Compared to the powder with elongated sphere or flower-like shapes, the nanowires showed a higher Li-ion capacity and a better cycle property.

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ABSTRACT
Y- and Si-based oxide nanopowders were synthesized by a hydrothermal reaction of Y or Si powders with NaOH or LiOH aqueous solution. Nanoparticles with different morphology such as elongated nanospheres, flower-like nanoparticles and nanowires were produced by a control of processing parameters, in particular, the starting composition of solution. The preliminary result of electrochemical examination showed that the hydrothermally processed nanowires exhibit high initial capacities of Li-ion storage: 653 mAh/g for Y(2)O(3) nanowires as anode materials and 186 mAh/g for Li(2)Si(2)O(5) nanowires as cathode materials in a Li secondary cell. Compared to the powder with elongated sphere or flower-like shapes, the nanowires showed a higher Li-ion capacity and a better cycle property.

No MeSH data available.


Li-ion storage property of the Si-based specimen (No. 4) as cathode materials in Li rechargeable cell: charge capacity versus cycle number and its first charge profile
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Figure 6: Li-ion storage property of the Si-based specimen (No. 4) as cathode materials in Li rechargeable cell: charge capacity versus cycle number and its first charge profile

Mentions: The synthesized nanopowders were electrochemically tested as anode materials for Y-based system (specimen No. 1 and 2) and as cathode materials for Si-based system (specimen 4) in Li-ion cells. The testing for anode materials was conducted over the voltage range of 0.01–3.0 V versus a Li/Li+ counter electrode. The discharge capacity of Y-based nanowire (specimen No. 2) was 653 mAh/g at first cycle but reduced to 533 mAh/g during charge (Fig. 5a). The difference might stem from the formation of a SEI film (solid electrolyte interface) on the surface of the nanowires, consuming irreversibly a certain amount of Li-ions. The Li-ion intercalation capacity was relatively well stabilized upon cyclying: 513 and 472 mAh/g after second and tenth cycle, respectively. The values are higher than that of conventional carbon-based anode materials (372 mAh/g) in Li-ion batteries. Compared to the nanowires, the anode made from the slightly spherical nanopowders exhibited a lower discharge capacity with a poor retention upon repeated cycles (Fig. 5b). The higher discharge capacity of nanowires might be related to their higher surface area compared with spherical particles. For cathode materials, hydrothermally Si-based nanowires were examined by charge–discharge test over the voltage range of 2.5–3.5 V versus a Li/Li+ counter electrode (Fig. 6). The charge capacity of the Si-based nanowire after the first cycle was 186 mAh/g, showing higher value than that of conventional Li–Mn–O or Li–Co–O cathode materials with relatively good cycle property.


Hydrothermally Processed Oxide Nanostructures and Their Lithium-ion Storage Properties.

Ahn JH, Kim YJ, Wang G - Nanoscale Res Lett (2010)

Li-ion storage property of the Si-based specimen (No. 4) as cathode materials in Li rechargeable cell: charge capacity versus cycle number and its first charge profile
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2964464&req=5

Figure 6: Li-ion storage property of the Si-based specimen (No. 4) as cathode materials in Li rechargeable cell: charge capacity versus cycle number and its first charge profile
Mentions: The synthesized nanopowders were electrochemically tested as anode materials for Y-based system (specimen No. 1 and 2) and as cathode materials for Si-based system (specimen 4) in Li-ion cells. The testing for anode materials was conducted over the voltage range of 0.01–3.0 V versus a Li/Li+ counter electrode. The discharge capacity of Y-based nanowire (specimen No. 2) was 653 mAh/g at first cycle but reduced to 533 mAh/g during charge (Fig. 5a). The difference might stem from the formation of a SEI film (solid electrolyte interface) on the surface of the nanowires, consuming irreversibly a certain amount of Li-ions. The Li-ion intercalation capacity was relatively well stabilized upon cyclying: 513 and 472 mAh/g after second and tenth cycle, respectively. The values are higher than that of conventional carbon-based anode materials (372 mAh/g) in Li-ion batteries. Compared to the nanowires, the anode made from the slightly spherical nanopowders exhibited a lower discharge capacity with a poor retention upon repeated cycles (Fig. 5b). The higher discharge capacity of nanowires might be related to their higher surface area compared with spherical particles. For cathode materials, hydrothermally Si-based nanowires were examined by charge–discharge test over the voltage range of 2.5–3.5 V versus a Li/Li+ counter electrode (Fig. 6). The charge capacity of the Si-based nanowire after the first cycle was 186 mAh/g, showing higher value than that of conventional Li–Mn–O or Li–Co–O cathode materials with relatively good cycle property.

Bottom Line: Y- and Si-based oxide nanopowders were synthesized by a hydrothermal reaction of Y or Si powders with NaOH or LiOH aqueous solution.The preliminary result of electrochemical examination showed that the hydrothermally processed nanowires exhibit high initial capacities of Li-ion storage: 653 mAh/g for Y(2)O(3) nanowires as anode materials and 186 mAh/g for Li(2)Si(2)O(5) nanowires as cathode materials in a Li secondary cell.Compared to the powder with elongated sphere or flower-like shapes, the nanowires showed a higher Li-ion capacity and a better cycle property.

View Article: PubMed Central - HTML - PubMed

ABSTRACT
Y- and Si-based oxide nanopowders were synthesized by a hydrothermal reaction of Y or Si powders with NaOH or LiOH aqueous solution. Nanoparticles with different morphology such as elongated nanospheres, flower-like nanoparticles and nanowires were produced by a control of processing parameters, in particular, the starting composition of solution. The preliminary result of electrochemical examination showed that the hydrothermally processed nanowires exhibit high initial capacities of Li-ion storage: 653 mAh/g for Y(2)O(3) nanowires as anode materials and 186 mAh/g for Li(2)Si(2)O(5) nanowires as cathode materials in a Li secondary cell. Compared to the powder with elongated sphere or flower-like shapes, the nanowires showed a higher Li-ion capacity and a better cycle property.

No MeSH data available.