Fabrication and directed assembly of magnetic Janus rods

Here, the preparation of Janus rods formed by growing silica rods on the surface of seed particles using a wet-chemical method is demonstrated, in which Fe3O4 microspheres are used as the seed particles. It is found that the morphology and aspect ratio of the Janus rods can be tuned by multiple experimental parameters, such as the size of the seed particles, reagent concentration and reaction time and temperature. In addition, directed assembly of the Janus rods is performed under an external magnetic field after a surface hydrophobization modification of the rods.