Selective and controlled synthesis of α- and β-cobalt hydroxides in highly developed hexagonal platelets
Selective and controlled synthesis of α- and β-cobalt hydroxides in highly developed hexagonal platelets
复制标题
DOI：
10.1021/ja0523338
复制
发表时间：
2005-10-12
影响因子：
15
通讯作者：
Sasaki, T
中科院分区：
文献类型：
--
作者：
Liu, ZP;Ma, RZ;Sasaki, T
我们报道了以六亚甲基四胺为水解剂，通过均匀沉淀法可控合成α-和β-Co（OH）（2）单晶片晶。α-和β-Co（OH）（2）六方片晶的宽度为几微米，厚度约为15 nm，分别在90 ℃下，在存在和不存在NaCl的情况下，在相当稀的CoCl 2溶液中可重复地产生。通过改变CoCl 2和NaCl浓度来实现产物的相和尺寸控制。偏光显微镜观察显示这些高纵横比血小板的胶体悬浮液的清晰的液晶性。所制备的α-Co（OH）（2）含有层间氯离子，并与各种无机或有机阴离子插层，保持了其高结晶度和六方片状形貌。
We report on the controlled synthesis of single-crystal platelets of alpha- and beta-Co(OH)(2) via homogeneous precipitation using hexamethylenetetramine as a hydrolysis agent. The alpha- and beta-Co(OH)(2) hexagonal platelets of several micrometers in width and about 15 nm in thickness were reproducibly yielded in rather dilute CoCl2 solutions in the presence and absence of NaCl at 90 degrees C, respectively. The phase and size control of the products were achieved by varying both CoCl2 and NaCl concentrations. Polarized optical microscope observations revealed clear liquid crystallinity of colloidal suspensions of these high aspect-ratio platelets. The as-prepared alpha-Co(OH)(2) containing interlayer chloride ions was intercalated with various inorganic or organic anions, keeping its high crystallinity and hexagonal platelike morphology.