Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Combustion-synthesized sodium manganese (cobalt) oxides as cathodes for sodium ion batteries
AU - Bucher, Nicolas
AU - Hartung, Steffen
AU - Gocheva, Irina
AU - Cheah, Yan L.
AU - Srinivasan, Madhavi
AU - Hoster, Harry E.
PY - 2013/7
Y1 - 2013/7
N2 - We report on the electrochemical properties of layered manganese oxides, with and without cobalt substituents, as cathodes in sodium ion batteries. We fabricated sub-micrometre-sized particles of Na0.7MnO2 + z and Na0.7Co0.11Mn0.89O2 + z via combustion synthesis. X-ray diffraction revealed the same layered hexagonal P2-type bronze structure with high crystallinity for both materials. Potentiostatic and galvanostatic charge/discharge cycles in the range 1.5-3.8 V vs. Na | Na+ were performed to identify potential-dependent phase transitions, capacity, and capacity retention. After charging to 3.8 V, both materials had an initial discharge capacity of 138 mA h g(-1) at a rate of 0.3 C. For the 20th cycle, those values reduced to 75 and 92 mA h g(-1) for Co-free and Co-doped samples, respectively. Our findings indicate that earlier works probably underestimated the potential of (doped) P2-type Na0.7MnO2 + z as cathode material for sodium ion batteries in terms of capacity and cycle stability. Apart from doping, a simple optimization parameter seems to be the particle size of the active material.
AB - We report on the electrochemical properties of layered manganese oxides, with and without cobalt substituents, as cathodes in sodium ion batteries. We fabricated sub-micrometre-sized particles of Na0.7MnO2 + z and Na0.7Co0.11Mn0.89O2 + z via combustion synthesis. X-ray diffraction revealed the same layered hexagonal P2-type bronze structure with high crystallinity for both materials. Potentiostatic and galvanostatic charge/discharge cycles in the range 1.5-3.8 V vs. Na | Na+ were performed to identify potential-dependent phase transitions, capacity, and capacity retention. After charging to 3.8 V, both materials had an initial discharge capacity of 138 mA h g(-1) at a rate of 0.3 C. For the 20th cycle, those values reduced to 75 and 92 mA h g(-1) for Co-free and Co-doped samples, respectively. Our findings indicate that earlier works probably underestimated the potential of (doped) P2-type Na0.7MnO2 + z as cathode material for sodium ion batteries in terms of capacity and cycle stability. Apart from doping, a simple optimization parameter seems to be the particle size of the active material.
KW - RECHARGEABLE LITHIUM BATTERIES
KW - INTERCALATION ELECTRODES
KW - ELECTROCHEMICAL-BEHAVIOR
KW - ENERGY-STORAGE
KW - NA
KW - PHASE
KW - CHALLENGES
KW - SUBSTITUTION
KW - DIFFRACTION
KW - PERFORMANCE
U2 - 10.1007/s10008-013-2047-x
DO - 10.1007/s10008-013-2047-x
M3 - Journal article
VL - 17
SP - 1923
EP - 1929
JO - Journal of Solid State Electrochemistry
JF - Journal of Solid State Electrochemistry
SN - 1432-8488
IS - 7
ER -