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通过一种新型的溶胶-凝胶法制备了纳米尺寸的Na_(0.5)Bi_(2.5)Nb_2O_9(NBN)粉体,该方法中应用配位化学路线将Nb2O5经过K3NbO4中间体过程转变为可溶性铌作为铌源。X射线衍射分析表明溶胶-凝胶法合成了纯相的铋层结构Na_(0.5)Bi_(2.5)Nb_2O_9(NBN),属于A2_am空间群,精修的晶胞参数为a=0·5478 nm,b=0.5472 nm和c=2.5185 nm。透射电镜分析表明合成的纳米产物呈片状形貌,平均粒径为50nm左右。电子衍射和高分辨透射电镜均证实产物结晶性良好,形成了单晶结构。NBN本征的层状结构有利于晶体沿二维方向进行生长,并最终形成纳米片。
Nanosized Na 0.5 Bi 2.5 Nb 2 O 9 (NBN) powders were prepared by a novel sol-gel method. In this method, the coordination chemical route was used to convert Nb 2 O 5 into soluble niobium through the K 3 NbO 4 intermediate process Niobium source. X-ray diffraction analysis showed that pure phase bismuth layer structure Na 0.5 Nb 2.5 Nb 2 O 9 (NBN) was synthesized by sol-gel method and belongs to the space group A2_am. The refined unit cell parameters are a = 0.54778 nm, b = 0.5472 nm and c = 2.5185 nm. Transmission electron microscopy showed that the synthesized nano-products were flaky morphology, the average particle size of about 50nm. Both electron diffraction and high-resolution transmission electron microscopy confirmed the crystallinity of the product was good and formed a single crystal structure. NBN intrinsic layered structure is conducive to two-dimensional crystal growth direction, and the final formation of nano-sheets.