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Synthesis and Structure of A3gaho4 (A=Ba, Sr) Oxyhydride Materials

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Synthesis and Structure of A3gaho4 (A=Ba, Sr) Oxyhydride Materials 2020/11/11 Synthesis and Structure of A3GaHO4 (A=Ba, Sr) Oxyhydride Materials NUR IKA PUJI AYU Supervisors: Takashi Kamiyama (IMS, KEK, SOKENDAI) Genki Kobayashi (IMSS, NINS, SOKENDAI) Department of Material Structure Science School of High Energy Accelerator Science The Graduate University of Advance Study, SOKENDAI 1 Introduction METAL HYDRIDES Hydrides In inorganic solids, the H- has the following characteristics[1]: Properties and applications a. The polarizable; - Highly reductive b. The size is flexible; - Hydrogen Storage materials c. Large mobility and labile - Ionic Conductor r=~130pm – 153pm in metal hydride character of the H–. 1. Saline Hydrides 2. Metallic Hydrides 3. Covalent Hydrides Dominant ionic bonding Rise to metallic conductivity LiH, NaH, KH, RbH, CsH BeH2, MgH2, CaH2, SrH2, BaH2 TiH ZrH , ScH , YH , LaH , NaMgH , RbCaH , etc x, x 2 2 2 3 3 etc [2] Smithson et.al Physical Review B 66 144107 (2002) 2 1 2020/11/11 Oxyhydrides Partial substitution of oxygen ions by hydride. The first reported oxyhydrides LaHO (1982) prepared by solid-state synthesis at 900oC under pure hydrogen[13]. Oxyhydrides Preparation Methods a) Highly reductive condition b) Without transferring electron from the hydrides. Direct Solid State Reaction (SSR) Indirect SSR or Topotactic High Pressure (~1-7GPa) Relatively low pressure (H2 gas) High Temperature Relatively low Temperature (T< ~600oC) Stoichiometric composition Non-stoichiometric, depends on the heating Synthesis time : ~ 1-2.5 hours time (about 2 days – 15 days) Small amount of sample (less than 1 gr) Possible to prepare several gram samples 3 Oxyhydrides Partial substitution of oxygen ions by hydride. The first reported oxyhydrides LaHO (1982) prepared by solid-state synthesis at 900oC under pure hydrogen[13]. Oxyhydrides Properties and applications Physical properties Catalysis H– conduction SrVO2H SrVO3 Pressure induced insulator to metal transition [3] Yamamoto, T, et. al. ,Nat. Commun. 8 (2017) [4] Kobayashi, Y, et.al. J. Am.Chem. Soc, 139, 18240-18246 (2017) [5] Kobayashi, G., et. al. AAS Sci. Rep. 351, 1314–1318 (2016) 4 2 2020/11/11 Reported Oxyhydrides BaTiO3-xHx Sr Co O H (insulator)[9] [6] LaSrMnO3.3Hx0.7 3 2 4.33 0.84 (semiconduct) [8] [9] semiconductor (SG, 33K) LaSrCoO3H0.7 (AFM) [11] insulator BaVO2.1H0.9 NdNiOxHy (semiconduct) [7], metal Sr2VO3H (AFM) Electropositive cations p-block element Oxyhydrides ? 5 Sample Preparation Characterizations a. SXRD, Spring-8 BL02B2 Powder diffractometer at RT 5 AO + AH2 + Ga2O3 ➔ 2 A3GaHO4 (A=Ba, Sr) Sample holder : glass capillary ø 0.2 mm Solid state reaction under 2GPa and 800oC b. Neutron diffraction, BL09 SPICA, J-Parc at RT. Sample holder : vanadium can ø 0.6 cm Planetary ball milling 150 rpm Pelletizing The high-pressure cell assembly High pressure and high temperature sintering and [13] Kobayashi, Y., Hernandez, O., Tassel, C. & quenching Kageyama, Sci. Technol. Adv. Mater. 18, 905–918 c. TG-DTA under Ar and O2 (2017). 6 3 2020/11/11 Crystal Structure Model of A3GaHO4(A=Ba, Sr) [14] Adopted from the crystal structure of Sr3GaO4F . Tetragonal I4/mcm A= Ba, Sr Atom Site Symmetry coordinate A1 4a 422 0, 0, ! ! A2 8h m.2m x, x+ , 0 # Ga 4b -42m 0, !, ! # H 4c 4/m.. 0, 0 ,0 ! O 16l ..m x, x+ , z # 7 7 ModelE H1 BVS Calculation[15] Ba3GaHO4 Sites Wyckf BVS from SXRD BVS from ND Ba1 Ba1 4a 1.36 1.37 Ba2 8h 2.30 2.20 Ba2 Ga 4b 2.82 2.73 H1 4c 1.09 0.96 GaO4 Ba1 Local O1 16l 1.40 1.35 ordering Sr3GaHO4 Ba1 Sr1 Sites Wyckf BVS from SXRD BVS from ND Sr1 4a 1.20 1.20 Sr2 8h 1.72 1.68 Ba2 Sr2 Ga 4b 2.66 2.77 H H 4c 0.79 0.78 H O 16l 1.67 1.68 8 8 4 2020/11/11 9 After TG _Ar a=b= 7.27588 Å c= 11.651263 Å a=b= 7.308876 Å c= 11.749465 Å 10 5 2020/11/11 11 11 Structure Study of Hydride conductor material Ba2LiH3O Order-Disorder transition and Superlattice structure Ba2LiH3O 12 6 2020/11/11 Future Work - Motivation First Reported pure H conductor La2LiHO3 7 Path 1 : Heqà Oeq Path 2 : Heq à Heq Path 3 : Heqà Oap Path 4 : Heqà interstitial site Path 5 : interstitial sites à Oap Path 6 : H à H int int Superstructure of K2NiF4 type structure oxyhydride? Path 7: O à H eq eq MEM Analysis? [16] Kobayashi, G., Hinuma, Y., Matsuoka, S. & Watanabe, A. Pure H – [17] Fjellvåg, Ø. S., Armstrong, J., Vajeeston, P. & Sjåstad, A. O.. J. conduction in oxyhydrides. 351, 1314–1318 (2016). Phys. Chem. Lett. 9, 353–358 (2018). 13 BL09Spica_ASC_RT (004) Tetragonal I4/mmm (110) Ba1 (116) (105) (202) (114) (103) Ba2LiH3O BL09Spica_ASC_RT Orthorhombic Superlattice peaks (splitting) 14 7 2020/11/11 Intermediate Temperature Experiment at BL09Spica Superlattice Structure 583K ~295K (RT) 300K (RT) Ba1.8LiH2.8O0.9 15 Crystal structure Crystal structure Ba1.8LiH2.8O0.9 Ba1.8LiH2.8O0.9 RT 583K Equatorial Anions Equatorial Anions H1 0.77(3) H1 0.869(18) H2 0.84(3) H2 0.831(18) H3 0.76(3) H3 0.879(18) H4 0.83(3) H4 0.841(18) Apical Anions Apical Anions H5 0.927(3) H5 0.900(3) H6 0.927(3) H6 0.900(3) O1 0.837(3) O1 0.810(3) O2 0.837(3) O2 0.810(3) 16 16 8 2020/11/11 300K 583K fy MEM n latio Could notCalcu satis Iso.level:+5, -2 Deuterated sample? Iso.level:+5, -2 ITERATION = 1056 ITERATION = 5979 LAMBDA = 1.38921e-03 LAMBDA = 5.88520e-05 C = 9.98771e-01 C = 9.99949e-01 17 Summary • New oxyhydrides of A3GaHO4 (A = Sr, Ba) have been synthesized by solid state reactions under high pressure 2GPa at 800oC. Synchrotron X-ray and neutron data revealed that the series adopt layered structures of tetragonal I4/mcm in which H– and O2– are ordered. • The preliminary study of superstructure of Ba1.8LiH2.8O0.9 has been done at intermediate temperature has been done at BL09 Spica. For further MEM analysis, deuteration is necessary to obtain better neutron data. 18 18 9 2020/11/11 Referrences [1] H. Kageyama, K. Hayashi, K. Maeda, J.P. Attfield, Z. Hiroi, J.M. Rondinelli, K.R. Poeppelmeier, Expanding frontiers in materials chemistry and physics with multiple anions, Nat. Commun. 9 (2018). doi:10.1038/s41467-018-02838-4. [2] Smithson et.al Physical Review B 66 144107 (2002) [3] T. Yamamoto, D. Zeng, T. Kawakami, V. Arcisauskaite, K. Yata, M.A. Patino, N. Izumo, J.E. McGrady, H. Kageyama, M.A. Hayward, The role of π-blocking hydride ligands in a pressure-induced insulator-to-metal phase transition in SrVO2H, Nat. Commun. 8 (2017). doi:10.1038/s41467-017-01301-0. [4] Y. Kobayashi , Y. Tang, T. Kageyama, H. Yamashita, N. Masuda, S. Hosokawa, H. Kageyama, Titanium-Based Hydrides as Heterogeneous Catalysts for Ammonia Synthesis, J. Am. Chem. Soc. 139 (2017) 18240–18246. doi:10.1021/jacs.7b08891. [5] G. Kobayashi, Y. Hinuma, S. Matsuoka, A. Watanabe, Pure H – conduction in oxyhydrides, 351 (2016) 1314–1318. [6] Bouilly, G., et. al. Electrical Properties of Epitaxial Thin Films of Oxyhydrides ATiO3−xHx (A = Ba and Sr). Chem. Mater. 2015, 27, 6354−6359. [7] Takafumi, Y., et. al. Selective Hydride Occupation in BaVO3−xHx (0.3 ≤ x ≤ 0.8) with Face- and Corner-Shared Octahedra Chem. Mater., 2018, 30 (5), pp 1566–1574. [8] Tassel, C., Goto, Y., et. al. High-Pressure Synthesis of ManganeseOxyhydride with Partial Anion Order. Angew. Chem. Int. Ed. 2016, 55, 9667-9670. [9] Helps, R. M., et. al. Sr3Co2O4.33H0.8: An Extended Transition Metal Oxide-hydride. Inorg. Chem. 2010, 49, 11062-11068. [10] Patino, M. A., Zeng, D., et. al. Extreme Sensitivity of a Topochemical Reaction to Cation Substitution: SrVO2H. Inorg. Chem. 2018, 57, 2890-2898. 19 Referrences [11] T. Onozuka, A. Chikamatsu, T. Katayama, T. Fukumura, T. Hasegawa, Formation of defect-fluorite structured NdNiO: XHy epitaxial thin films via a soft chemical route from NdNiO3 precursors, Dalt. Trans. 45 (2016) 12114–12118. doi:10.1039/c6dt01737a. [12] B. Huang, J.D. Corbett, Ba21Ge2O5H24 and Related Phases. A Corrected Structure Type and Composition for a Zintl Phase Stabilized by Hydrogen, Inorg. Chem. 37 (1998) 1892–1899. doi:10.1021/ic971339y. [13] Y. Kobayashi, O. Hernandez, C. Tassel, H. Kageyama, New chemistry of transition metal oxyhydrides, Sci. Technol. Adv. Mater. 18 (2017) 905–918. doi:10.1080/14686996.2017.1394776. [14] Quilty, C. D., Avdeev, M., Driskell, J. D. & Sullivan, E. Structural characterization and photoluminescence in the rare earth-free oxy-fluoride anti-perovskites Sr3−xBi2x/3AlO4F and Sr3−xBi2x/3GaO4F. Dalt. Trans. 46, 4055–4065 (2017). [15] C. D. Quilty, M. Avdeev, J. D. Driskell and E. Sullivan, Dalt. Trans., 2017, 46, 4055–4065. [16] Kobayashi, G., Hinuma, Y., Matsuoka, S. & Watanabe, A. Pure H – conduction in oxyhydrides. 351, 1314–1318 (2016). [17] Fjellvåg, Ø. S., Armstrong, J., Vajeeston, P. & Sjåstad, A. O. New Insights into Hydride Bonding, Dynamics, and Migration in La2LiHO3Oxyhydride. J. Phys. Chem. Lett. 9, 353–358 (2018). 20 10.
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