Surface-functionalized monolayered nanodots of a transition metal oxide and their properties.

Lateral size, surface chemistry, and properties are varied in inorganic monolayers based on a transition metal-oxide. A variety of inorganic monolayers with their emergent properties have been studied in recent decades. However, it is not easy to tune the lateral size, surface chemistry, and dispersibility of monolayers by typical synthetic methods. In the present work, a new approach is developed for the simultaneous surface functionalization and exfoliation of the precursor nanocrystals in a nonpolar organic medium. We obtained monolayered nanodots of a titanium oxide less than 5 nm in lateral size with surface functionalization by an alkylamine (C14H29NH2) and dihydroxynaphthalene (DHN) in toluene. The bandgap energy of the monolayers was changed by the lateral size and surface functionalization. The present study suggests versatile potentials of the monolayers with tuned size, surface chemistry, and properties.