Millifluidic flow reactor for reproducible seed-mediated nanoparticle synthesis

Despite the great progress in the colloidal syntheses of plasmonic metal nanoparticles, batch processes still face a general limitation toward achieving large-scale production and reproducibility, due to insufficient control over reagent addition conditions and other reaction parameters, such as mixing rate, temperature, etc. Flow reactors provide the opportunity to counteract the limitations of traditional batch nanomaterials synthesis. We demonstrate the use of a purposely devised millifluidic flow reactor for the seeded growth of monodisperse gold nanoparticles with high process control and batch-to-batch reproducibility. This system offers versatility toward the synthesis of various gold nanoparticle shapes and dimensions, as demonstrated here for nanospheres, nanorods, and nanostars.