초록 |
All-inorganic perovskite nanocrystals have shown as excellent optoelectronic materials with high efficiencies in photovoltaic cell and light emitting applications. Here we present the droplet-based modular microfluidic system for the step-wise synthesis and in-situ anion-exchange in highly luminescent perovskite nanocrystals of cesium lead halide (CsPbX3, X = Cl, Br, I). Microreactor provide small reaction volumes that are more homogeneous with correspond to concentration, temperature, and mass transport, resulting to a better control of the reaction parameters. By introducing the halide ions (i.e., Cl and I) in the primary generated CsPbBr3 colloidal solution, the bright photoluminescence can be changed over the entire visible spectral region simultaneously. Furthermore, we demonstrate that fast anion-exchange can be generated various types of perovskite nanocrystals with uniform morphology and high monodispersity. |