Authors: H-Y Fan, K. Yang, J.P. Gabaldon, D.M. Boye, T. Sigmon, K.J. Malloy and C.J. Brinker
Affilation: Sandia National Laboratories, United States
Pages: 765 - 768
Keywords: nanocrystal self-assembly, water-soluble, superlattice, arrays
In this presentation, we will report a simple and general method to synthesize ordered, three-dimensional, transparent gold NC/silica superlattices through self-assembly of water-soluble gold NC-micelles and soluble silica under controlled kinetic conditions. NC-micelles were synthesized according to our recently developed surfactant encapsulation method (Fan et al. Science 304, 567-571, 2004). Low pH reaction condition ensures spin solution homogeneity and stability, facilitating the self-assembly of soluble silica and NC-micelles into ordered gold NC/silica films. Under basic conditions, well-shaped “crystal” structures were obtained. These “crystal” structures consist of ordered fcc gold NC arrays inside silica. In addition to silica, TiO2 and silsesquioxane have been used to tune dielectrics between gold NCs. The robust, 3-D NC superlattice films and solids are of interest for development of collective optical and electronic phenomena, and, importantly, for the integration of NC arrays into device architectures. Initial experiments on a MOS capacitor fabricated with an ordered gold NC/silica ‘oxide’ demonstrated charge storage on the gold NCs and discharge behavior dominated by electron transport within the ordered gold NC array. The method opens a new pathway to the fabrication of 3-D NC superlattice inside inorganic framework with tunable dielectric.