Large‐Scale Synthesis of InP/ZnS Quantum Dots Using Continuous Flow Chemistry

InP quantum dots (QDs) are emerging as promising cadmium‐free alternatives for various applications, including lighting and display technologies. However, the large‐scale, continuous production of high‐quality InP QDs faces several challenges, and robust synthetic approaches applicable on standard flow platforms are lacking. One persisting key issue is the identification of suitable precursors for the continuous‐flow production. Herein, we develop the flow synthesis of InP QDs in a noncoordinating solvent, using trioctylphosphine complexes of indium and zinc chloride as metal precursors, along with tris(oleylamino)phosphine as the phosphorus source. By systematically varying the flow rate and reaction temperature, we achieve precise control over the QD size in the 2–4 nm range. Employing the single‐molecular precursor zinc diethyldithiocarbamate to synthesize a ZnS shell enables the gram‐scale continuous production of InP/ZnS core/shell QDs with a photoluminescence quantum yield of 54%. Solid‐state NMR analysis provides insights into the surface chemistry of the QDs during shell growth, revealing the intermediate formation of an oxide layer acting as a buffer between InP and ZnS. Our findings not only present a scalable approach for the continuous synthesis of InP/ZnS QDs but also deepen the understanding of their surface chemistry, paving the way for further improvements.