Process Intensification through Data-Rich Approach: Dynamic Exploration of Continuous Flow Quantum Dot Parameter Space

A quantum dot (QD) is a high performing semiconductor material, exhibiting more than one tunable optoelectronic property through precise control of size, morphology, and composition. Recently, colloidal synthesis of II-VI and III-V Quantum Dot (QD) nanomaterial has been successfully achieved through the hot-injection and heat up synthesis batch process technique, resulting in near unity photoluminescence quantum yield and enhanced photostability. To broaden QD integration in the renewable energy, display, and chemical industry, the search for more efficient QD nanomaterial and the corresponding sustainable manufacturing route has received increased attention in both academia and industry. This exploration through the QD synthesis space can be drastically accelerated by combining continuous flow chemistry and autonomous experimentation with reaction and data intensification. Specifically, applying process intensification in the form of microscale flow chemistry has demonstrated the ability to enhance heat and mass transfer through an increased surface to volume ratio, shortening startup and shutdown time, lowering reaction time, and decreasing precursor consumption, when compared to traditional batch chemistry. Moreover, continuous flow chemistry is capable of facile integration with data-rich experimental methodology, generating accurate Big Experimental Data for any precise physical and chemical condition. However, most analyses performed in continuous flow chemistry discard the transient information obtained during experiment startup and shutdown, as well as between each experiment, consequently limiting data acquisition to only the steady state condition. Recuperating the discarded, transient information through data-rich experimental methodology can not only utilize data more effectively, but also significantly expedite the pace of research acceleration. In this work, we demonstrate the importance of analyzing transient phenomena for intensification of the experimental design space associated with nanoparticle synthesis through the systemic evaluation and optimization of the single stage continuous flow synthesis of an exemplary QD, cadmium selenide (CdSe). Additionally, we present reduced raw material consumption and lowered reaction timescales, relative to traditional steady state flow experimentation, thereby achieving considerable intensification of the development and discovery of colloidal functional material. By embracing flow chemistry’s compatibility with data-rich experimental methodology and extensively studying dynamic behavior, the pathway for accelerating experimentation is notably fortified, providing greater precision and efficacy for navigation of the complexity associated with QD discovery and development.