Confined Synthesis of Ultrathin Amorphous Metal-Oxide Nanosheets

As a new member of metal oxide family, two-dimensional (2D) amorphous metal oxide nanosheets have attracted considerable research interest in various fields, because of their unique surface electronic structure. However, some 2D amorphous metal oxide nanosheets produced by strong acid weak alkali salts (such as FeCl3, ZrCl4, CrCl3, SnCl4, and AlCl3) are difficult to synthesize, because of their tendency to precipitate and aggregate under facile conditions. Thus, developing a common route to prepare these 2D amorphous metal oxide nanosheets is urgently needed. Herein, we report a universal method to synthesize a series of 2D amorphous metal oxide, including Fe2O3, Cr2O3, ZrO2, SnO2, and Al2O3. In this method, lamellar oleate is introduced as a host matrice to restrict the ion exchange reaction that occurs between Cu2O and metal ions. By controlling calcination temperature to remove the oleate, the corresponding 2D amorphous metal oxide ultrathin nanosheets are successfully obtained. This facial method may open a new avenue to fabricate promising 2D amorphous metal oxide nanosheets for practical applications.