Here, the preparation of Janus rods formed by growing a silica rod on the surface of seed particles using a wet-chemical method is demonstrated, in which Fe3O4 microspheres are used as the seed particle. 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 particle, reagent concentration and reaction time and temperature. In addition, directed assembly of the Janus rods is preformed under an external magnetic field after a surface hydrophobilization modification of the rods. 

New J. Chem., 2016