Low temperature synthesis of(oxy) nitride

当考虑氮化物作为功能材料，如光催化剂和荧光粉，局部结构的影响，如表面形貌和晶体中的缺陷是远远超过那些块体性能的平均值更显着。因此，当氮化物的研究从传统转向新的。例如从氮化物作为环境惰性材料的研究到氮化物作为功能材料的研究。有必要从一开始就重新评估氮化物合成的方法。基于上述观点，我们开展了氨法合成功能氮化物相关材料，特别是光催化材料的研究。总之，我们在超临界氨和氨基钠中于600℃成功制备了结晶性良好的LaTaON_2钙钛矿。氨法制备的LaTaON_2的光催化性能比固相反应法制备的LaTaON_2有所提高。在超临界氨中以氨基钠为矿化剂反应前后，其形貌和粒径发生了显著变化。因此，可以认为该反应是在NH_3-NaNH_2溶液中进行的。这种方法可以推广到其他氧氮基团的合成。

When considering nitrides as functional materials such as photocatalysts and phosphor, the effects of local structures such as surface morphology and defects in crystals are far more significant than those of the mean values of bulk properties. Therefore, when shifting the study of nitrides from the conventional to the new. such as from the study of nitrides as environmentally inert materials to nitrides as functional materials. it is necessary to re-evaluate, from the beginning, the methodology of nitride synthesis. Based on the above perspectives, we conduct our study with emphasis on the synthesis of functional nitride related materials, especially photocatalysts materials, using the ammonothermal method. In conclusion, we have succeeded to prepare LaTaON_2 perovskite with well crystallinity in supercritical ammonia with sodium amide at 600℃. And the photocatalytic properties of LaTaON_2 prepared by ammonothermal method have improved in comparison of LaTaON_2 by solid state reaction. Before and after reaction in supercritical ammonia with sodium amide as a mineralizer, the morphology and particle size was dramatically changed. So it may be considered this reaction proceed in NH_3-NaNH_2 solution as a solvent. This approach could be extended to synthesis of other oxynitrid groups.