Facile and controlled synthesis of 3D nanorods-based urchinlike and nonosheets-based flowerlike cobalt basic salt nanostructures

We report the controlled synthesis of four kinds of cobalt basic salts with different morphologies and colors (pink, blue, green, and lavender) using urea as a hydrolysis agent in the presence of block copolymer P123. Li2SO4 and LiCl were used as salt additives to control the type of cobalt basic, salts. It was found that the amount of urea plays a critical role in the synthesis of cobalt basic salts with different phases. Two of them exhibit interesting three-dimensional urchinlike and flowerlike morphology assembled from nanorods (pink) and nanosheets (blue), respectively. The present work suggests that it is possible to directly grow three-dimensional-ordered assemblies built from one-dimensional or two-dimensional cobalt basic salt narrostructures through a one-step aqueous solution-phase chemical route under controlled conditions.