Moon Keon-Ho, Kim Jung-Mi, Sohn Youngku, Cho Dae Won, Kim Young-Il, Avdeev Maxim
Department of Energy Convergence Engineering, Graduate School, Yeungnam University, Gyeongsan 38541, Republic of Korea.
Dalton Trans. 2016 Apr 7;45(13):5614-21. doi: 10.1039/c6dt00310a. Epub 2016 Feb 26.
New complex perovskite oxynitrides AMg0.2Ta0.8O2.6N0.4 (A = Sr, Ba) were synthesized by reacting A5Ta4O15 with MgCl2 in flowing NH3. The formation of AMg0.2Ta0.8O2.6N0.4 can be described as the cooperative insertion of Mg(2+) + 2N(3-) and the release of 2O(2-) from the layered oxide, A5Ta4O15. Rietveld refinement of the neutron and synchrotron X-ray diffraction patterns indicated that BaMg0.2Ta0.8O2.6N0.4 is simple cubic (Pm3[combining macron]m) and SrMg0.2Ta0.8O2.6N0.4 is body-centered tetragonal (I4/mcm), isostructural with BaM0.2Ta0.8O2.8N0.2 and SrM0.2Ta0.8O2.8N0.2 (M = Li, Na), respectively. The nitrogen in SrMg0.2Ta0.8O2.6N0.4 is partially ordered favoring the c-axial site over the ab-plane of the tetragonal cell, which is a different O/N order pattern from that of SrLi0.2Ta0.8O2.8N0.2 and SrNa0.2Ta0.8O2.8N0.2. The group of simple and complex perovskites, ATaO2N, ALi0.2Ta0.8O2.8N0.2, ANa0.2Ta0.8O2.8N0.2, and AMg0.2Ta0.8O2.6N0.4 (A = Sr, Ba) covers the band gap range, 1.9-2.4 eV, and the color ranges from yellow to dark brown.
通过在流动的氨气中使A5Ta4O15与MgCl2反应，合成了新型复合钙钛矿氧氮化物AMg0.2Ta0.8O2.6N0.4（A = Sr，Ba）。AMg0.2Ta0.8O2.6N0.4的形成可描述为Mg(2+) + 2N(3-)的协同插入以及层状氧化物A5Ta4O15中2O(2-)的释放。对中子和同步加速器X射线衍射图谱进行的Rietveld精修表明，BaMg0.2Ta0.8O2.6N0.4为简单立方结构（Pm3[combining macron]m），SrMg0.2Ta0.8O2.6N0.4为体心四方结构（I4/mcm），分别与BaM0.2Ta0.8O2.8N0.2和SrM0.2Ta0.8O2.8N0.2（M = Li，Na）同构。SrMg0.2Ta0.8O2.6N0.4中的氮部分有序，在四方晶胞的c轴位置比ab面更受青睐，这与SrLi0.2Ta0.8O2.8N0.2和SrNa0.2Ta0.8O2.8N0.2的O/N有序模式不同。简单和复合钙钛矿组ATaO2N、ALi0.2Ta0.8O2.8N0.2、ANa0.2Ta0.8O2.8N
