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A 3.8-V earth-abundant sodium battery electrode.

Barpanda P, Oyama G, Nishimura S, Chung SC, Yamada A - Nat Commun (2014)

Bottom Line: Rechargeable lithium batteries have ushered the wireless revolution over last two decades and are now matured to enable green automobiles.However, their performance is limited owing to low operating voltage and sluggish kinetics.Here we report a hitherto-unknown material with entirely new composition and structure with the first alluaudite-type sulphate framework, Na2Fe2(SO4)3, registering the highest-ever Fe(3+)/Fe(2+) redox potential at 3.8 V (versus Na, and hence 4.1 V versus Li) along with fast rate kinetics.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan [2] Unit of Element Strategy Initiative for Catalysts and Batteries, ESICB, Kyoto University, Kyoto 615-8510, Japan [3] Materials Research Center, Indian Institute of Science, Bangalore 560012, India [4].

ABSTRACT
Rechargeable lithium batteries have ushered the wireless revolution over last two decades and are now matured to enable green automobiles. However, the growing concern on scarcity and large-scale applications of lithium resources have steered effort to realize sustainable sodium-ion batteries, Na and Fe being abundant and low-cost charge carrier and redox centre, respectively. However, their performance is limited owing to low operating voltage and sluggish kinetics. Here we report a hitherto-unknown material with entirely new composition and structure with the first alluaudite-type sulphate framework, Na2Fe2(SO4)3, registering the highest-ever Fe(3+)/Fe(2+) redox potential at 3.8 V (versus Na, and hence 4.1 V versus Li) along with fast rate kinetics. Rare-metal-free Na-ion rechargeable battery system compatible with the present Li-ion battery is now in realistic scope without sacrificing high energy density and high power, and paves way for discovery of new earth-abundant sustainable cathodes for large-scale batteries.

No MeSH data available.


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Electrode properties of Na2−xFe2(SO4)3 in Na cell.(a) Galvanostatic charging and discharging profiles of Na2−xFe2(SO4)3 cathode cycled between 2.0 and 4.5 V at a rate of C/20 (2 Na in 20 h) at 25 °C. First (1st) cycle is shown in dashed black line, and 2nd–5th cycle in solid black lines. (Inset) The differential galvanostatic profiles (dQ/dV) of Na2−xFe2(SO4)3 cathode showing two distinctive peaks during the first charge and broader three peaks upon subsequent discharging/charging processes. (b) Capacity retention upon cycling up to 30 cycles under various rate of C/20 (2 Na in 20 h) to 20C (2 Na in 3 min). (Inset) The discharge curves of Na2−xFe2(SO4)3 as a function of rate (from C/20 to 20C). Before each discharge, the cells were charged at C/10 to 4.2 V.
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f3: Electrode properties of Na2−xFe2(SO4)3 in Na cell.(a) Galvanostatic charging and discharging profiles of Na2−xFe2(SO4)3 cathode cycled between 2.0 and 4.5 V at a rate of C/20 (2 Na in 20 h) at 25 °C. First (1st) cycle is shown in dashed black line, and 2nd–5th cycle in solid black lines. (Inset) The differential galvanostatic profiles (dQ/dV) of Na2−xFe2(SO4)3 cathode showing two distinctive peaks during the first charge and broader three peaks upon subsequent discharging/charging processes. (b) Capacity retention upon cycling up to 30 cycles under various rate of C/20 (2 Na in 20 h) to 20C (2 Na in 3 min). (Inset) The discharge curves of Na2−xFe2(SO4)3 as a function of rate (from C/20 to 20C). Before each discharge, the cells were charged at C/10 to 4.2 V.

Mentions: The electrode properties of as-synthesized Na2Fe2(SO4)3 were examined with no further optimization such as particle downsizing or carbon coating. The primary particle size was evaluated to be ~100–200 nm by scanning electron microscope observation (Supplementary Fig. 1), and the electrode loading was ca. 3 mg cm−2. The corresponding voltage-capacity profiles for first few cycles between 2.0–4.5 V (versus Na/Na+) at a rate of C/20 (25 °C) is shown in Fig. 3a. The Na2Fe2(SO4)3 cathode offers an average potential of 3.8 V (versus Na/Na+), which is the highest-ever Fe3+/Fe2+ redox potential in any materials environment. The well-known NASICON-type Fe(III)2(SO4)3 (ref. 18) has same composition with desodiated Na2Fe2(SO4)3 in the present study, but NASICON phase delivers an average potential of 3.3 V (versus Na/Na+) upon Na insertion19.


A 3.8-V earth-abundant sodium battery electrode.

Barpanda P, Oyama G, Nishimura S, Chung SC, Yamada A - Nat Commun (2014)

Electrode properties of Na2−xFe2(SO4)3 in Na cell.(a) Galvanostatic charging and discharging profiles of Na2−xFe2(SO4)3 cathode cycled between 2.0 and 4.5 V at a rate of C/20 (2 Na in 20 h) at 25 °C. First (1st) cycle is shown in dashed black line, and 2nd–5th cycle in solid black lines. (Inset) The differential galvanostatic profiles (dQ/dV) of Na2−xFe2(SO4)3 cathode showing two distinctive peaks during the first charge and broader three peaks upon subsequent discharging/charging processes. (b) Capacity retention upon cycling up to 30 cycles under various rate of C/20 (2 Na in 20 h) to 20C (2 Na in 3 min). (Inset) The discharge curves of Na2−xFe2(SO4)3 as a function of rate (from C/20 to 20C). Before each discharge, the cells were charged at C/10 to 4.2 V.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109020&req=5

f3: Electrode properties of Na2−xFe2(SO4)3 in Na cell.(a) Galvanostatic charging and discharging profiles of Na2−xFe2(SO4)3 cathode cycled between 2.0 and 4.5 V at a rate of C/20 (2 Na in 20 h) at 25 °C. First (1st) cycle is shown in dashed black line, and 2nd–5th cycle in solid black lines. (Inset) The differential galvanostatic profiles (dQ/dV) of Na2−xFe2(SO4)3 cathode showing two distinctive peaks during the first charge and broader three peaks upon subsequent discharging/charging processes. (b) Capacity retention upon cycling up to 30 cycles under various rate of C/20 (2 Na in 20 h) to 20C (2 Na in 3 min). (Inset) The discharge curves of Na2−xFe2(SO4)3 as a function of rate (from C/20 to 20C). Before each discharge, the cells were charged at C/10 to 4.2 V.
Mentions: The electrode properties of as-synthesized Na2Fe2(SO4)3 were examined with no further optimization such as particle downsizing or carbon coating. The primary particle size was evaluated to be ~100–200 nm by scanning electron microscope observation (Supplementary Fig. 1), and the electrode loading was ca. 3 mg cm−2. The corresponding voltage-capacity profiles for first few cycles between 2.0–4.5 V (versus Na/Na+) at a rate of C/20 (25 °C) is shown in Fig. 3a. The Na2Fe2(SO4)3 cathode offers an average potential of 3.8 V (versus Na/Na+), which is the highest-ever Fe3+/Fe2+ redox potential in any materials environment. The well-known NASICON-type Fe(III)2(SO4)3 (ref. 18) has same composition with desodiated Na2Fe2(SO4)3 in the present study, but NASICON phase delivers an average potential of 3.3 V (versus Na/Na+) upon Na insertion19.

Bottom Line: Rechargeable lithium batteries have ushered the wireless revolution over last two decades and are now matured to enable green automobiles.However, their performance is limited owing to low operating voltage and sluggish kinetics.Here we report a hitherto-unknown material with entirely new composition and structure with the first alluaudite-type sulphate framework, Na2Fe2(SO4)3, registering the highest-ever Fe(3+)/Fe(2+) redox potential at 3.8 V (versus Na, and hence 4.1 V versus Li) along with fast rate kinetics.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan [2] Unit of Element Strategy Initiative for Catalysts and Batteries, ESICB, Kyoto University, Kyoto 615-8510, Japan [3] Materials Research Center, Indian Institute of Science, Bangalore 560012, India [4].

ABSTRACT
Rechargeable lithium batteries have ushered the wireless revolution over last two decades and are now matured to enable green automobiles. However, the growing concern on scarcity and large-scale applications of lithium resources have steered effort to realize sustainable sodium-ion batteries, Na and Fe being abundant and low-cost charge carrier and redox centre, respectively. However, their performance is limited owing to low operating voltage and sluggish kinetics. Here we report a hitherto-unknown material with entirely new composition and structure with the first alluaudite-type sulphate framework, Na2Fe2(SO4)3, registering the highest-ever Fe(3+)/Fe(2+) redox potential at 3.8 V (versus Na, and hence 4.1 V versus Li) along with fast rate kinetics. Rare-metal-free Na-ion rechargeable battery system compatible with the present Li-ion battery is now in realistic scope without sacrificing high energy density and high power, and paves way for discovery of new earth-abundant sustainable cathodes for large-scale batteries.

No MeSH data available.


Related in: MedlinePlus