Quantum dots (QDs) are widely used in many applications, e.g., lighting and display, photovoltaics, biology, and sensors, due to their size-dependent optical and electronic properties. Despite their expanding applications, most of them still remain in the laboratory stage. One of the major obstacles limiting the industrialscale application is the lack of scalable processes for the preparation of QD materials at high quality and reasonable costs. Targeting this challenge, firstly a scalable process for the continuous flow synthesis of InP/ZnS QDs, the model system studied in this thesis, is developed. Specifically, the continuous flow synthesis platform is established and the batch synthesis of InP/ZnS QDs using cheaper and safer aminophosphine has been successfully transferred to a continuous flow synthesis with high reproducibility. A two-step continuous process is designed, incorporating a high-temperature microreactor for the nucleation and growth of InP core QDs and a second high-temperature microreactor for the ZnS shell growth. InP and InP/ZnS QDs synthesized from the developed continuous processes exhibit broad size tunability, which enables emission from green to red, and comparable photoluminescence quantum yield (PLQY). Secondly, for the knowledge-based process design, a predictive model based on population balance equations for InP formation is developed, enabled by the reproducible experimental results from an automated robotic synthesis platform. Key parameters, including precursor concentration, reaction time and temperature, are investigated experimentally and numerically. The simulated mean particle size, solid concentration, and particle size distribution exhibit a good agreement with the experimental ones, and the simulated activation energy for InP growth also align very well with the literature-reported experimental value. These results validate the developed model and demonstrate its predictivity. Thirdly, to unlock the optical performance of InP/ZnS QDs from the developed scalable process using a single-source shell precursor, the shelling process using zinc diethyldithiocarbamate as the shell precursor is investigated. The relationship among the shelling process, the formation of ZnS by homogeneous nucleation and optical properties of InP/ZnS QDs is revealed, which deepens the understanding of ZnS shell formation and paves the way for large-scale production of highly luminescent InP/ZnS QDs. Lastly, to realize complex structures using QDs as building blocks which enables new optical properties for broad applications, the phase transfer of InP/ZnS QDs from organic non-polar solvent (e.g., n-hexane) to polar solvent (e.g., water) is developed and the preparation of the InP/ZnS-ZIF- 8 composite is attempted. Briefly, a ligand exchange procedure is successfully developed, resulting water-dispersible InP/ZnS QDs. Based on this method, the InP/ZnS-ZIF-8 composite is prepared by the synthesis of ZIF-8 in the presence of InP/ZnS QDs. As a proof of concept for potential application in ratiometric temperature sensing, the temperature-dependent dual-emission of the composite is demonstrated.

To summarize, this thesis develops a scalable process for the continuous flow synthesis of luminescent InP/ZnS QDs, advances the model-based process design, deepens the understanding of the ZnS shelling process using a single-source precursor and demonstrates the temperature-dependent dual-emission of the InP/ZnS-ZIF-8 composite as a promising material for ratiometric temperature sensors. These contributions pave the way to the future industrial-scale applications of environmentally-friendly III-V QDs in various fields.