Development of a novel microfluidic reactor for highly controlled synthesis of semiconductor nanocrystals

Despite numerous advancements in the understanding of the unique properties of semiconductor nanocrystals, challenges associated with current production strategies have prevented these materials from finding widespread application. Current batch-wise synthesis methods offer only limited ability to probe the processes occurring during the formation of individual nanocrystals and no synthesis method yet exists that is capable of achieving widespread production of nanocrystals. Microfluidic reaction systems present an attractive alternative to conventional synthesis techniques because they afford greater control over local reaction environments than is possible in conventional batch-wise methods, and could ultimately increase production capabilities through massive parallelization. Here, the unique challenges associated with microfluidic synthesis of semiconductor nanocrystals are discussed, along with a presentation of an innovative microfluidic reactor concept that directly addresses the limitations of conventional microfluidic reaction systems for this purpose.;The reactor discussed here features a droplet-based two-phase flow design that eliminates the dispersion-induced broadening of the particle size distribution that is characteristic of other microfluidic designs. The flow channels in the design are arranged to spiral in and out of novel reaction coin structures that are designed to allow the thermal profile of the reactor to be tailored to the specific requirements of nanocrystal synthesis operations. A simplified prototype reactor has been constructed and tested to demonstrate the feasibility of the reactor concept. Broader impacts of the design concept with respect to the ability to permit unprecedented control over the size distribution of the particles are discussed.