TY - JOUR
T1 - First-principles study of X-ray absorption spectra in NaFeSo4F for exploring Na-ion battery reactions
AU - Momida, Hiroyoshi
AU - Kitajou, Ayuko
AU - Okada, Shigeto
AU - Oguchi, Tamio
N1 - Funding Information:
Acknowledgments This work was supported by the Elements Strategy Initiative for Catalysts and Batteries (ESICB) of the Ministry of Education, Culture, Sports, Science and Technology (MEXT). The computation in this work was partly carried out using the facilities of the Supercomputer Center, Institute for Solid State Physics, University of Tokyo. The Na, F, and Fe K-edge XANES spectra were obtained on the BL11 and BL12 beamlines at the SAGA Light Source with the approval of the Kyushu Synchrotron Light Research Center (proposal 1603014A, 1808066F).
Funding Information:
This work was supported by the Elements Strategy Initiative for Catalysts and Batteries (ESICB) of the Ministry of Education, Culture, Sports, Science and Technology (MEXT). The computation in this work was partly carried out using the facilities of the Supercomputer Center, Institute for Solid State Physics, University of Tokyo. The Na, F, and Fe K-edge XANES spectra were obtained on the BL11 and BL12 beamlines at the SAGA Light Source with the approval of the Kyushu Synchrotron Light Research Center (proposal 1603014A, 1808066F).
Publisher Copyright:
©2019 The Physical Society of Japan
PY - 2019
Y1 - 2019
N2 - By means of first-principles calculations, we study electronic and spectroscopic properties of NaFeSO4F, which has been expected recently to be a candidate cathode material for Na-ion batteries. The NaFeSO4F cathodes have been often synthesized from NaF and FeSO4 in experiments, and present structural stability analysis shows that NaFeSO4F is slightly more stable in energy than the two-phase mixture of NaF and FeSO4. An average voltage of NaFeSO4F cathode is theoretically estimated to be 3.08 V with respect to a metal Na anode, and that comes dominantly from electronic structure changes of Fe2+=Fe3+ in NaFeSO4F=FeSO4F. X-ray absorption spectra (XAS) near K-edges at Fe, Na, and F are calculated for NaFeSO4F and FeSO4F as the cathode materials in fully discharged and charged states, respectively, and also for NaF and FeSO4 as possible residual materials in actual cathodes. We show that XAS near K-edges, especially at F sites as well as Fe sites, provides us useful information to clarify battery reactions and structures in actual cathodes.
AB - By means of first-principles calculations, we study electronic and spectroscopic properties of NaFeSO4F, which has been expected recently to be a candidate cathode material for Na-ion batteries. The NaFeSO4F cathodes have been often synthesized from NaF and FeSO4 in experiments, and present structural stability analysis shows that NaFeSO4F is slightly more stable in energy than the two-phase mixture of NaF and FeSO4. An average voltage of NaFeSO4F cathode is theoretically estimated to be 3.08 V with respect to a metal Na anode, and that comes dominantly from electronic structure changes of Fe2+=Fe3+ in NaFeSO4F=FeSO4F. X-ray absorption spectra (XAS) near K-edges at Fe, Na, and F are calculated for NaFeSO4F and FeSO4F as the cathode materials in fully discharged and charged states, respectively, and also for NaF and FeSO4 as possible residual materials in actual cathodes. We show that XAS near K-edges, especially at F sites as well as Fe sites, provides us useful information to clarify battery reactions and structures in actual cathodes.
UR - http://www.scopus.com/inward/record.url?scp=85075553877&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85075553877&partnerID=8YFLogxK
U2 - 10.7566/JPSJ.88.124709
DO - 10.7566/JPSJ.88.124709
M3 - Article
AN - SCOPUS:85075553877
VL - 88
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
SN - 0031-9015
IS - 12
M1 - 124709
ER -