An oxyhydride of BaTiO3 exhibiting hydride exchange and electronic conductivity

Article metrics


In oxides, the substitution of non-oxide anions (F,S2−,N3− and so on) for oxide introduces many properties, but the least commonly encountered substitution is where the hydride anion (H) replaces oxygen to form an oxyhydride. Only a handful of oxyhydrides have been reported, mainly with electropositive main group elements1,2,3,4,5 or as layered cobalt oxides with unusually low oxidation states6,7. Here, we present an oxyhydride of the perhaps most well-known perovskite, BaTiO3, as an O2−/H solid solution with hydride concentrations up to 20% of the anion sites. BaTiO3−xHx is electronically conducting, and stable in air and water at ambient conditions. Furthermore, the hydride species is exchangeable with hydrogen gas at 400 °C. Such an exchange implies diffusion of hydride, and interesting diffusion mechanisms specific to hydrogen may be at play. Moreover, such a labile anion in an oxide framework should be useful in further expanding the mixed-anion chemistry of the solid state.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: BaTiO3 and its oxyhydride.
Figure 2: Characterization using diffraction (X-ray, neutron and electron) and 1H NMR.
Figure 3: Mass spectrometry of gaseous species during deuteride exchange.
Figure 4: Excerpts from neutron diffraction patterns of BaTiO2.4H0.6 before and after deuteration.


  1. 1

    Malaman, B. & Brice, J. F. Etude structurale de l’hydruro-oxyde LaHO par diffraction des rayons X et par diffraction des neutrons. J. Solid State Chem. 53, 44–54 (1984).

  2. 2

    Clark, N. J. & Wu, E. Hydrogen absorption by M5X3 phase Zr–Al compounds. J. Less Common Metals 142, 145–154 (1988).

  3. 3

    Huang, B. & Corbett, J. D. Ba3AlO4H: Synthesis and structure of a new hydrogen-stabilized phase. J. Solid State Chem. 141, 570–575 (1998).

  4. 4

    Huang, B. & Corbett, J. D. Ba21Ge2O5H24 and related phases. A corrected structure type and composition for a Zintl phase stabilized by hydrogen. Inorg. Chem. 37, 1892–1899 (1998).

  5. 5

    Hayashi, K., Matsuishi, S., Kamiya, T., Hirano, M. & Hosono, H. Light-induced conversion of an insulating refractory oxide into a persistent electronic conductor. Nature 419, 462–465 (2002).

  6. 6

    Hayward, M. A. et al. The hydride anion in an extended transition metal oxide array: LaSrCoO3H0.7 . Science 295, 1882–1884 (2002).

  7. 7

    Helps, R. M., Rees, N. H. & Hayward, M. A. Sr3Co2O4.33H0.84: An extended transition metal oxide-hydride. Inorg. Chem. 49, 11062–11068 (2010).

  8. 8

    Poeppelmeier, K. A mixed oxide-hydride perovskite. Science 295, 1849 (2002).

  9. 9

    Steinsvik, S., Larring, Y. & Norby, T. Hydrogen ion conduction in iron-substituted strontium titanate, SrTi1−xFexO3−x/2 (0<=x<=0.8). Solid State Ionics 143, 103–116 (2001).

  10. 10

    Poulsen, F. W. Speculations on the existence of hydride ions in proton conducting oxides. Solid State Ionics 145, 387–397 (2001).

  11. 11

    Norby, T., Widerøe, M., Glöckner, R. & Larring, Y. Hydrogen in oxides. Dalton Trans. 3012–3018 (2004).

  12. 12

    Chen, Y., Gonzalez, R., Schow, O. E. & Summers, G. P. Charge and mass transfer involving hydrogen in MgO crystals thermochemically reduced at high temperatures. Phys. Rev. B 27, 1276–1282 (1983).

  13. 13

    Janotti, A. & van de Walle, C. G. Hydrogen multicentre bonds. Nature Mater. 6, 44–47 (2007).

  14. 14

    Du, M-H. & Biswas, K. Anionic and hidden hydrogen in ZnO. Phys. Rev. Lett. 106, 115502 (2011).

  15. 15

    Pantazis, P., Maloney, J., Wu, D. & Fraser, S. E. Second harmonic generating (SHG) nanoprobes for in vivo imaging. Proc. Natl Acad. Sci. USA 107, 14535–14540 (2010).

  16. 16

    Andersson, S. & Magnéli, A. Diskrete Titanoxydphasen im Zusammensetzungsbereich TiO1.75–TiO1.90 . Naturwissenschaften 43, 495–496 (1956).

  17. 17

    Hayashi, K. Heavy doping of H ion in 12CaO·7Al2O3 . J. Solid State Chem. 184, 1428–1432 (2011).

  18. 18

    Shima, T. et al. Molecular heterometallic hydride clusters composed of rare-earth and d-transition metals. Nature Chem. 3, 814–820 (2011).

  19. 19

    Verbraeken, M. C., Viana, H. A. L., Wormald, P. & Irvine, J. T. S. A structural study of the proton conducting B-site ordered perovskite Ba3Ca1.18Ta1.82O8.73 . J. Phys. Condens. Matter 23, 234111 (2011).

  20. 20

    Maekawa, H., Kashii, N., Kawamura, J-I., Hinatsu, Y. & Yamamura, T. High temperature 1H NMR study of proton conducting oxide SrCe0.95Y0.05H0.004O3−δ . Solid State Ionics 122, 231–236 (1999).

  21. 21

    Blundred, G. D., Bridges, C. A. & Rosseinsky, M. J. New oxidation states and defect chemistry in the pyrochlore structure. Angew. Chem. Int. Ed. 43, 3562–3565 (2004).

  22. 22

    Tsujimoto, Y. et al. Infinite-layer iron oxide with a square-planar coordination. Nature 450, 1062–1065 (2007).

  23. 23

    Hayward, M. A., Green, M. A., Rosseinsky, M. J. & Sloan, J. Sodium hydride as a powerful reducing agent for topotactic oxide deintercalation: Synthesis and characterization of the nickel(I) oxide LaNiO2 . J. Am. Chem. Soc. 121, 8843–8854 (1999).

  24. 24

    Bridges, C. A., Fernandez-Alonso, F., Goff, J. P. & Rosseinsky, M. J. Observation of hydride mobility in the transition-metal oxide hydride LaSrCoO3H0.7 . Adv. Mater. 18, 3304–3308 (2006).

  25. 25

    Iwazaki, Y., Suzuki, T. & Tsuneyuki, S. Negatively charged hydrogen at oxygen-vacancy sites in BaTiO3: Density-functional calculation. J. Appl. Phys. 108, 083705 (2010).

  26. 26

    Nowick, A. S. Exploring the low-temperature electrical relaxation of crystalline oxygen-ion and protonic conductors. Solid State Ionics 136–137, 1307–1314 (2000).

  27. 27

    Karkamkar, A. et al. Thermodynamic and structural investigations of ammonium borohydride, a solid with a highest content of thermodynamically and kinetically accessible hydrogen. Chem. Mater. 21, 4356–4358 (2009).

  28. 28

    Ohoyama, K. et al. The new neutron powder diffractometer with a multi-detector system for high-efficiency and high-resolution measurements. Jpn. J. Appl. Phys. 37, 3319–3326 (1998).

  29. 29

    Petricek, V., Dusek, M. & Palatinus, L. Jana 2006. The Crystallographic Computing System (Institute of Physics, 2006).

Download references


We thank S. Mitsuoka, H. Ohkubo, F. Takeiri, K. Ohoyama, W. Paulus, M. Takata and T. Nishiyama for assistance with various aspects. This work was supported by the Japan Society for the Promotion of Science (JSPS) through its ‘Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST) Program’; Grant-in-Aid for Science Research in the Priority Areas (No. 19052004); and Grant-in-Aid for Scientific Research (A) (No. 22245009) from the Ministry of Education, Culture, Sports, Science and Technology of Japan. Y.T. and A.K. were supported by JSPS Research Fellowships for Young Scientists.

Author information

H.K. designed the study, with advice from M.T. The initial synthesis was performed by Y.T., M.M. and A.K., with T.S., T.Y. and M.O. optimizing conditions. T.S., T.Y., A.K. and Y.T. obtained the X-ray and neutron diffraction data with assistance from J.e.K. and N.T., and electron diffraction patterns were obtained by Y. Kusano. The presence of hydride was proposed by O.J.H. and T.R. and confirmed by O.J.H., Z.L. and Y.T. Rietveld refinements were initially performed by Y.T. and then finalized by O.J.H. NMR spectra were measured by Y.N. and Y. Mogami. with advice from K.T. Magnetic susceptibility was measured by Y.T. and M.M. The deuterium exchange reactions were conceived by S.H. and Y. Kobayashi, and performed by T.S.; the acid digestion analysis was performed by Y. Kobayashi. A.F., Y. Matsushita, M.I. and K.Y. also provided assistance with various aspects. All authors discussed the results; Y. Kobayashi wrote the manuscript, with discussions mainly with H.K., O.J.H. and M.T.

Correspondence to Hiroshi Kageyama.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 576 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Kobayashi, Y., Hernandez, O., Sakaguchi, T. et al. An oxyhydride of BaTiO3 exhibiting hydride exchange and electronic conductivity. Nature Mater 11, 507–511 (2012) doi:10.1038/nmat3302

Download citation

Further reading