Literature Seminar:

Oxynitrides and their ability to be synthesized are an important facet in the solid-state chemistry field. Their properties are more tunable than in their single-anion counterparts as anions exhibit different characteristics (i.e. electronegativity) that contribute to the overall properties of the material. However, difficulty in their synthesis arises due to the intrinsic stability of nitrogen. The current technique to make these materials requires high-temperature (800-1300°C) ammonolysis (treatment with NH₃). However, this technique involves a highly reducing atmosphere and N^3- has low ability to incorporate into the lattice due to its large charge. The idea of a labile ligand as seen in coordination chemistry is extended in the solid-state to exchange the labile hydride in BaTiO_3-xH_x for nitrogen to make BaTiO_3-xN_2x/3 (an oxynitride). The H^– ion can be exchanged with N^3- through low temperature (<500°C) treatment with NH₃. In this talk, I will discuss why this exchange occurs and what characterization techniques were done to prove this exchange. The extension of this low-temperature hydride technique to other systems will also be discussed.

Yajima, T.; Takeiri, F.; Aidzu, K.; Akamatsu, H.; Fujita, K.; Yoshimune, W.; Ohkura, M.; Lei, S.; Gopalan, V.; Tanaka, K.; Brown, C.M.; Green, M.A.; Yamamoto, T.; Kobayashi, Y.; Kageyama, H. A labile hydride strategy for the synthesis of heavily nitridized BaTiO₃. Nat. Chem. 2015, 7, 1017-1023