T. Kambe, N. Haruta, T. Imaoka, K. Yamamoto
Nature Commun. 2017, 8, 2046.Al13−超原子の液相合成
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.
T. Kambe, A. Watanabe, T. Imaoka, K. Yamamoto
Angew. Chem. Int. Ed. 2016, 55, 13151-13154.
Dendritic phosphors were obtained by the stepwise integration of BiCl3 in phenylazomethine dendrimers. The bismuth-coordinated phenylazomethines displayed photoluminescence at 500–800 nm, and the intensity could be tuned by changing the stoichiometry of BiCl3 and the dendrimer. This phosphor did not show serious luminescence quenching even though the local concentration of BiCl3 in the dendrimer was as high as 20 M, and luminescence was also observed in the solid state. The absorption and emission properties could be reversibly switched by addition of a Lewis base or under electrochemical redox control, which induced the reversible complexation of BiCl3 in the dendrimer.