1 nm sized materials with strong electronic interactions has drawn significant interest for its unique properties. The bottom-up synthesis enables the functionalization and property control. Here, I will present our research on the solution-phase synthesis of metal complex nanosheets, superatoms and borophene-oxide derivatives.

Metal-complex nanosheets were synthesized by reacting metal ions and organic ligands at a biphasic interface.Their structures were revealed by XRD and electron microscopy measurements. These samples were found to exhibit two-dimensional conduction, while also possessing redox properties derived from the metal complexes. Superatoms were realized using dendrimers, a class of dendritic polymers. By controlling the number of metal atoms through coordination, clusters containing 13 atoms, as well as superatoms incorporating various elements, were successfully synthesized.

A layered crystal composed of boron-based monolayer structures was also synthesized. Single-crystal structural analysis revealed alternating stacks of anionic oxidized borophene and potassium cations. Due to this ionic nature, the material could be dissolved in solvents, allowing the preparation of substances with thicknesses ranging from a single layer to several layers.Furthermore, it was discovered that this material exhibited liquid-crystalline functionality upon heat treatment. Unlike conventional organic liquid crystals, this system could operate over a broader temperature range.In addition, substitution of interlayer metal cations was achieved. By focusing on the mobility of these interlayer cations, we identified a function enabling significant enhancement of capacitance.