Nanoparticles made of precious metals (gold, silver, platinum, etc.) are useful for biomedical therapies, energy generation, and improving the efficiency of chemical reactions. Current techniques for manufacturing these nanoparticles, however, rely on slow and costly laboratory-scale chemical reactions, making metal nanoparticles cost-prohibitive for their most promising applications. Reactions performed in small batches in the lab guarantee high particle quality and uniformity. This quality and uniformity would be lost if the reaction volumes were increased to the industrial scale. This award supports research in the development of microfluidic chemical reactors for generating nanoparticles. Microfluidic chemical reactors handle very small volumes of chemicals in channels that are smaller than a millimeter across. Because of their small size, they can produce nanoparticles with the same quality and uniformity as the laboratory-scale reactions currently used. The goal of the research supported by this award is to understand how to operate many microfluidic reactors simultaneously, allowing for large quantities of nanoparticles to be produced in an automated, continuous manner while maintaining the quality of these particles. The technology developed here will facilitate the efficient and sustainable industrial-scale production of metal nanoparticles. This project will be integrated with an educational outreach program that incorporates high school and community college students as active participants in the research.
While nanofabrication in microreactors is an established technology, there are several challenges that need to be overcome to make it a sustainable industrial-scale process. This research will accomplish four objectives to overcome these challenges. (1) Development of sustainable ionic-liquid based chemistry for the fabrication of Pt and Rh nanoparticles. (2) Design of microfluidic surface coatings for maximized throughput of droplet flows. (3) Implementation of new droplet merger techniques to facilitate multistep (e.g., seeded growth) nanoparticle fabrication reactions. (4) Feedback control of highly parallelized systems of microreactors to facilitate industrial-scale yields. This award will advance knowledge at the intersection of diverse fields of study, facilitating the application of techniques from chemistry, chemical engineering, and microfabrication technology to develop fundamental principles for the scale up of nanoparticle manufacturing in continuous-flow microreactors. It will lead to the development of broadly adaptable schemes for the rational assembly and control of massively parallel microfluidic reactors and techniques for performing sustainable chemistry in these systems. The goal is a science-based approach to the design of industrial-scale, sustainable microreactor manufacturing systems.
