2021 Annual Meeting
In-Flow Facile Cation Doping of Metal Halide Perovskite Quantum Dots
Metal cation doping of all-inorganic metal halide perovskite (MHP) quantum dots (QDs) enables incorporation of new optical, optoelectronic, and/or magnetic properties into the pristine QDs. In this work, we present an ultrafast (< 2 s) metal cation doping strategy for all-inorganic MHP QDs. Specifically, we investigate the role of dopant concentration and ligand-to-solvent ratio on the kinetics and extent of metal cation doping of an exemplary MHP QDs, cesium lead chloride, using a modular microfluidic platform equipped with a translational spectral monitoring probe. Manganese (II) chloride, Oleylamine, and 1-octadecene were selected as the source of the metal cation dopant, ligand, and reaction solvent, respectively. We illustrate that the emission color of the doped MHP QDs can be tuned within the blue-violet to orange-red regions through tuning the dopant concentration. The in-flow cation doping of MHP QDs was precisely monitored through real-time in-situ UV-Vis absorption and photoluminescence spectroscopy. The unique translational spectral monitoring probe coupled with the time-to-distance transformation enabled by flow chemistry allowed us to monitor the progress of the metal cation doping at various residence times (i.e., reaction times). The benefits of conducting the metal cation doping of all-inorganic MHP QDs in flow, compared to batch reactors, are enhanced and precisely tunable mass transfer rates as well as time and resource savings. In addition, in-flow studies of colloidal synthesis and doping of QDs allows for faster and more predictable results, allowing for future prospects of on-demand precision synthesis of metal-cation doped QDs with desirable optical and optoelectronic properties for optoelectronic and photonic devices.