Lüdtke Tobias, Schmidt Alexander, Göbel Caren, Fischer Anna, Becker Nils, Reimann Christoph, Bredow Thomas, Dronskowski Richard, Lerch Martin
Institut für Chemie, TU Berlin , Straße des 17. Juni 135, D-10623 Berlin, Germany.
Inorg Chem. 2014 Nov 3;53(21):11691-8. doi: 10.1021/ic501726m. Epub 2014 Oct 13.
δ-TaON was prepared by reaction of gaseous ammonia with an amorphous tantalum oxide precursor. As a representative of the anatase structure (aristotype) it crystallizes in the tetragonal crystal system with lattice parameters a = 391.954(16) pm and c = 1011.32(5) pm. At temperatures between 800 and 850 °C an irreversible phase transformation to baddeleyite-type β-TaON is observed. While quantum-chemical calculations confirm the metastable character of δ-TaON, its transformation to β-TaON is kinetically controlled. The anion distribution of the anatase-type phase was studied theoretically. In agreement with previous studies, it was found that a configuration with maximal N-N distances is most stable. The calculated band edge energies indicate that δ-TaON is a promising photocatalytic material for redox reactions, e.g., water splitting.
δ-TaON通过气态氨与非晶态氧化钽前驱体反应制备而成。作为锐钛矿结构（原型）的代表，它结晶于四方晶系，晶格参数a = 391.954(16)皮米，c = 1011.32(5)皮米。在800至850°C的温度范围内，观察到向斜锆石型β-TaON的不可逆相变。虽然量子化学计算证实了δ-TaON的亚稳特性，但其向β-TaON的转变受动力学控制。从理论上研究了锐钛矿型相的阴离子分布。与先前的研究一致，发现具有最大N-N距离的构型最稳定。计算得到的带边能量表明，δ-TaON是一种用于氧化还原反应（如光解水）的有前景的光催化材料。
