Facet Specific Gold Tip growth on Semiconductor Nanorods

High quality CdS-Au and CdSe-Au hybrid nanocrystals have been developed via facile approaches. Gold tip growth onto II-VI nanorods has been shown to occur instantaneously both via a solution and spin cast method. Gold tip size and multiplicity can be varied by changing the starting gold chloride concentration or the reaction duration. Gold tip growth typically occurs at one end of the nanorod, however we recently observed that a variation in the reaction temperature leads to the growth of a tip on both ends of the nanorod. TEM analysis showed that the gold tip growth does not always occur centrosymmetrically on the rod tip, with growth occurring on either the (001) or the (101) facet depending on the respective sizes. Spin coating gold chloride solution onto a pre-deposited perpendicular oriented array of nanorods leads to individual gold growth at the tips of each nanorod.