Multiple Hydrogen-Bond-Assisted Self-Assembly of Semiconductor Nanocrystals on Silicon Surfaces and Nanowires

We report a versatile and modular approach to assemble a monolayer of semiconductor nanocrystals on silicon Surfaces. Bifunctional molecules containing at one end a tripod allylic anchor group, which allows robust attachment on Si-H terminated surfaces, and at the other end a group able to participate in Multiple hydrogen bonding are used for the assembly of small CdSe nanocrystals on flat silicon and silicon nanowires. The diaminotriazine-thymine pair was used as the hydrogen-bonding pair. The obtained structures (on nanowires and 2D silicon Surfaces) are characterized using infrared spectroscopy, X-ray photoelectron spectroscopy, optical microscopy, and non-contact AFM. We demonstrate that the chosen strategy is a powerful approach to modify the chemical and physical properties of nanowires.