Solution-phase synthesis of Al₁₃^- using a dendrimer template.

Abstract

Superatoms, clusters that mimic the properties of elements different to those of which they are composed, have the potential to serve as building blocks for unprecedented materials with tunable properties. The development of a method for the solution-phase synthesis of superatoms would be an indispensable achievement for the future progress of this research field. Here we report the fabrication of aluminum clusters in solution using a dendrimer template, producing Al₁₃^-, which is the most well-known superatom. The Al₁₃^- cluster is identified using mass spectrometry and scanning transmission electron microscopy, and X-ray photoelectron spectroscopy is used to measure the binding energies. The superatomic stability of Al₁₃^- is demonstrated by evaluating its tendency toward oxidation. In addition, the synthesis of Al₁₃^- in solution enables electrochemical measurements, the results of which suggest oxidation of Al₁₃^-. This solution-phase synthesis of Al₁₃^- superatoms has a significant role for the experimental development of cluster science.