The synthesis of three-dimensionally ordered, transparent gold-nanocrystal (NC)/silica superlattice thin films using the self-assembly (by spin-coating) of water-soluble gold nanocrystal micelles and soluble silica is reported by Fan and co-workers on p. 891. The robust, 3D NC/silica superlattice films are of interest for the development of collective optical and electronic phenomena, and, importantly, for the integration of NC arrays into device architectures.
Nanocrystals and their ordered arrays hold many important applications in fields such as catalysis, surface-enhanced Raman spectroscopy based sensors, memory storage, and electronic and optical nanodevices. Herein, a simple and general method to synthesize ordered, three-dimensional, transparent gold nanocrystal/silica superlattice thin films by self-assembly of gold nanocrystal micelles with silica or organosilsesquioxane by spin-coating is reported. The self-assembly process is conducted under acidic sol–gel conditions (ca. pH 2), ensuring spin-solution homogeneity and stability and facilitating the formation of ordered and transparent gold nanocrystal/silica films. The monodisperse nanocrystals are organized within inorganic host matrices as a face-centered cubic mesostructure, and characterized by transmission electron spectroscopy and X-ray diffraction.