Ammonia-Evaporation-Induced Synthetic Method for Metal (Cu, Zn, Cd, Ni) Hydroxide/Oxide Nanostructures

We report an ammonia-evaporation-induced synthetic method for metal (Ni, Cu, Zn, and Cd) hydroxide/oxide nanostructures including hierarchical CuO spheres with radiating nanoplates, densely branched ZnO nanowires, Cd(OH)₂ nanofibers, and Ni(OH)₂ nanoplates. One important feature of this mild and surfactant-free methodology is that these nanostructures grow in a dynamic environment with the continuous decrease of pH and ammonia concentration in the solution, which is responsible for the formation of the complex architectures. The obtained Cd(OH)₂ nanofibers and Ni(OH)₂ nanoplates can also be converted into oxides by a subsequent thermal treatment. In addition to the synthesis and mechanism studies, we have investigated the electrochemical reactivity of the CuO spheres, CdO nanofibers, and NiO nanoplates toward lithium and demonstrated their potential application as anode materials for lithium ion batteries.