Adsorption behaviors of V2O5 nanowires on binary mixed self-assembled monolayers

The adsorption behaviors of V2O5 nanowires on binary mixed self-assembled monolayers (SAMs) were investigated with variation of the mixing ratio of two differently terminated thiolates on Au. Hydroxyl-covered V2O5 nanowires showed a preferential adsorption on amine (NH2)-terminated thiolates over methyl (CH3)-terminated ones. However, on the binary mixed SAM of NH2- and CH3-terminated thiols, the adsorption behavior did not follow a simple expectation based upon the electrostatic interaction. The total number of adsorbed V2O5 nanowires increased with the mole fraction of NH2-terminated thiolates up to χNH2∼0.5, then it decreased with further increase of χNH2. The height distribution of adsorbed nanowires showed that the relative portion of the agglomerated wires thicker than 3.5 nm to individual wires thinner than 3.5 nm increased up to χNH2∼0.75 and then it decreased with further increase of χNH2. The dispersion of molecules with polar-functional groups as well as the molecular ordering of mixed SAMs is attributed to such adsorption behaviors of V2O5 nanowires.