Asymmetric Dimers Can Be Formed by Dewetting Half-Shells of Gold Deposited on the Surfaces of Spherical Oxide Colloids

作者：Lu Yu, Hui Xiong, Xuchuan Jiang, Younan Xia, Mara Goff Prentiss, George M. Whitesides · 发表于：Journal of the American Chemical Society · 年份：2003 · DOI：10.1021/ja0373014 · 被引用次数：204 · 研究领域：Pickering emulsions and particle stabilization、Photonic Crystals and Applications、Block Copolymer Self-Assembly

Asymmetric dimers consisting of gold microcrystals and spherical silica colloids have been fabricated by depositing thin films of gold onto the spherical colloids to form half-shells, followed by annealing at elevated temperatures. The capability and feasibility of this procedure have been demonstrated with silica and titania beads of 0.2-2 mum in diameter and gamma-Fe2O3/polystyrene@SiO2 core-shell particles 0.5 mum in size. The dimensions of gold microcrystals could be conveniently varied in the range of 100-650 nm by controlling the thickness of gold films and/or the diameter of the spherical colloids. This method provides another route to asymmetric dimers made of colloidal particles that could be different in size, chemical composition, surface functionality, density or sign of surface charge, bulk property, or a combination of these properties.