Multicomponent inorganic Janus particles with controlled compositions, morphologies, and dimensions.

We report a new protocol for the preparation of shape-controlled multicomponent particles comprising metallic (Au and Ti), magnetic (Ni), and oxide (SiO2, TiO2) layers. Our method allows for a precise control over the composition, shape, and size and permits fabrication of nonsymmetrical particles, whose opposite sides can be orthogonally functionalized using well-established organosilanes and thiol chemistries. Because of their unique geometries and surface chemistries, these colloids represent ideal materials with which to study nonsymmetrical self-assembly at the meso- and microscales.