Asymmetric Functional Colloids through Selective Hemisphere Modification

Miguel A. Correa-Duarte, Verónica Salgueiriño-Maceira, Benito Rodríguez-González, Luis M. Liz-Marzán, Adam Kosiorek, Witold Kandulski, and Michael Giersig

Adv. Mater., 2005, 17, 2014–2018

Core–shell colloids with two well-differentiated sides (see Figure) have been produced by a combination of electron beam evaporation (EBE) and polyelectrolyte-driven layer-by-layer (LbL) assembly. The colloids are patterned with different optical and magnetic functionalities through deposition of silica-coated gold nanoparticles and evaporation of gold and nickel, forming different thin films on opposite hemispheres.