Electrohydrodynamic Printing of PCL@CsPbBr3 Composite Fibers with High Luminescence for Flexible Displays

Metal halide perovskite quantum dots (PQDs) are widely used in the display field due to their excellent photoelectric properties, such as ultra-narrow half-peak widths and ultra-pure luminescence color purity. Inkjet printing, laser direct writing and electrospinning are all common methods for PQDs printing to prepare micropattern displays. In order to produce large-scale and high-resolution PQDs micropatterns, electrohydrodynamic (EHD) printing technology is capable of large-scale deposition of highly oriented nanofibers on rigid or pliable, flat or bent substrates with the advantages of real-time regulation and single control. Therefore, it has a lot of potential in the fabrication of pliable electronic devices for one-dimensional ordered light-emitting fibers. Polycaprolactone (PCL) as an EHD printing technology polymer material has the advantages of superior biocompatibility, a low melting point, saving energy and easy degradation. By synthesizing CsPbBr3 quantum dots (QDs) and PCL composite spinning stock solution, we used the self-built EHD printing platform to prepare the PCL@CsPbBr3 composite light-emitting optical fiber and realized the flexible display of high-resolution micropatterns in polydimethylsiloxane (PDMS) packaging. An x-ray diffractometer (XRD), scanning electron microscope (SEM) and photoluminescence (PL) were used to characterize and analyze the fiber’s morphology, phase and spectral characteristics. EHD printing technology may open up interesting possibilities for flexible display applications based on metal halide PQDs.