A new iron hydroxyl-phosphate, H2Fe14/3(PO4)4(OH)4 has been synthesized under hydrothermal conditions. In this compound, perpendicular chains formed by the face-sharing FeO6 form rod-packing structure. Only about 60% of the chain sites are occupied by iron atoms; other metals, such as manganese, nickel, zinc, can be incorporated into the chain either by filling in the vacancies and/or replacing some of the iron atoms. Reversible insertion and extraction of lithium into this compound shows it to be an excellent cathode material. At current density of 0.1 mA/cm2, 90 % of the theoretical capacity (176 mAh/g) can be obtained. The utilization was reduced to about 70 % on a ten-fold increase of current density. The electrochemical behavior is attributed to the 3-dimensional rod packing structure, where lithium can move freely even at high current densities inside the 3-dimensional framework without altering the host structure. Two of the protons in the lattice may be exchanged by lithium giving Li2Fe14/3(PO4)4(OH)4. These lithium atoms are not removable in electrochemical cycling and similar electrochemical property was found for these two compounds, suggesting an ion-exchange process for the lithiation.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
K. S. Nanjundaswamy, A. K. Padhi, J. B. Goodenough, S. Okada, H. Ohtsuka, H. Arai and J. Yamaki, Solid State Ionics 92, 1(1996).
C. Masquelier, A. K. Padhi, K. S. Nanjundaswamy and J. B. Goodenough, J. of Solid State Chem. 135, 228 (1998).
A. K. Padhi, K. S. Nanjundaswamy and J. B. Goodenough, J. Electrochem. Soc. 144, 1188 (1997).
A. K. Padhi, K. S. Nanjundaswamy, C. Masquelier, S. Okada and J. B. Goodenough, J. Electrochem. Soc. 144, 1609 (1997).
A. S. Andersson, B. Kalska, L. Haggstrom and J. O. Thomas, Solid State Ionics 130, 41 (2000).
Y. Song, S. Yang, P. Y. Zavalij and M. S. Whittingham, Mater. Res. Bull. 37, 1249 (2002).
Y. Song, P. Y. Zavalij, M. Suzuki and M. S. Whittingham, Inorg. Chem. 41, 5778 (2002).
M. Cavellec, G. Ferey, J. M. Greneche, J. Magnetism and Magnetic Mater. 167, 57 (1997).
Y. Song, N. A. Chernova, P. Y. Zavalij and M. S. Whittingham, Chem. Mater. (submitted).
Y. Song, P. Y. Zavalij and M. S. Whittingham, Electrochem. Comm. (submitted).
About this article
Cite this article
Song, Y., Zavalij, P.Y. & Stanley Whittingham, M. New Iron (III) Hydroxyl-Phosphate with Rod-packing Structure as Intercalation Materials. MRS Online Proceedings Library 756, 77 (2002). https://doi.org/10.1557/PROC-756-EE7.7