Selective Deposition of Metal Complex Nanocrystals onto the Surfaces of Organic Single Crystals Bearing Pyridine Moieties

Nanocrystals of a palladium complex 3 were deposited onto the specific surfaces of the single crystals of CT complex (CT1) between pyrene and naphthyldiimide bearing pyridine groups. They were characterized by X-ray powder diffraction (XRD) and scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (SEM-EDX). Nanocrystals of 3 were deposited selectively onto {011̅} faces. Comparison between the crystal structures and deposition preference of the crystal faces revealed that deposition of 3 occurred on the most hydrophobic face of the single crystals of CT1 that exposed no pyridine moieties. This indicated that accessibility or coordination of metal complexes to the pyridine moieties apparently suppressed deposition of the nanocrystals. As a result, the nanocrystals were easily deposited onto the hydrophobic crystal surfaces, and rapid growth provides the thin-film decoration of the selective crystal faces.