| Summary: | We investigated the nitridation of reduced BaTiO<sub>3</sub>, BaTiO<sub>2.60</sub>H<sub>0.08</sub>, corresponding to an oxyhydride with a large concentration of O defects (>10%). The material is readily nitrided under flowing N<sub>2</sub> gas at temperatures between 400 and 450 °C to yield oxynitrides BaTiO<sub>2.6</sub>N<i><sub>x</sub></i> (<i>x</i> = 0.2−0.22) with a slightly tetragonally distorted perovskite structure, <i>a</i> ≈ 4.01 and <i>c</i> ≈ 4.02 Å, and Ti partially remaining in the oxidation state III. The tetragonal structure was confirmed from Raman spectroscopy. <sup>14</sup>N MAS NMR spectroscopy shows a single resonance at 270 ppm, which is typical for perovskite transition metal oxynitrides. However, largely different signal intensity for materials with very similar N content suggests N/O/vacancy ordering when prolonging nitridation times to hours. Diffuse reflectance UV-VIS spectroscopy shows a reduction of the intrinsic band gap to 2.4–2.45 eV compared to BaTiO<sub>3</sub> (~3.2 eV). Mott-Schottky measurements confirm n-type conductivity and reveal a slight negative shift of the conduction band edge from –0.59 V (BaTiO<sub>3</sub>) to ~–0.65 eV.
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