Fluorescent Microarrays of in Situ Crystallized Perovskite Nanocomposites Fabricated for Patterned Applications by Using Inkjet Printing

Abstract

Perovskite materials have exhibited promising potential for universal applications including backlighting, color conversion, and anticounterfeiting labels fabricated using solution processes. However, owing to the tendency of those materials to have uncontrollable morphologies and to form large crystals, they cannot be utilized in discontinuous microminiaturization, which is crucial for practical optoelectronic applications. In this research, combining the effects of adding polyvinylpyrrolidone (PVP), precisely controlling the inkjet printing technique, and using a postprocessing procedure, we were able to fabricate in situ crystallized perovskite–PVP nanocomposite microarrays with perfect morphologies. The viscosity of the perovskite precursor increased with the addition of PVP, eliminating the outward capillary flow that induces the coffee-ring effect. In addition, because of the presence of metallic bonds with the CO groups in PVP and the spatial confinement of such a polymer, we were able to fabricate regulated CsPbBr3 nanocrystals capped with PVP and with a uniform size distribution. The as-printed patterns showed excellent homogeneity on a macroscale and high reproducibility on a microscale; furthermore, those patterns were invisible in the ambient environment, compatible with flexible substrates, and cost-efficient to produce, indicating that this technique holds promising potential for applications such as anticounterfeiting labels.

Optoelectronic Perovskite Synapses for Neuromorphic Computing

“…All‐inorganic perovskite materials have attracted wide attention in the academic field due to their narrow half‐peak width, high photoluminescence quantum yield, easy regulation of the luminescence wavelength, and good thermal stability. Today, all‐inorganic perovskite materials are widely used in photovoltaic devices, such as solar cells, photodetectors, and light‐emitting diodes.…”

Advances in Inkjet‐Printed Metal Halide Perovskite Photovoltaic and Optoelectronic Devices

“…In general, solvents within the curve wet the substrate, whereas solvents outside the curve dewet . A surface treatment or cleaning cycle may change the wetting behavior, as well as storage under different atmospheric conditions, especially in case of transition metal oxide contact layers …”

“…Of particular importance for printing are additives that change the ink properties, especially viscosity, surface tension, and wetting behavior, which can be adjusted by liquid surfactants or polymers . Moreover, additives change the solution chemistry, the formation of complexes and colloids and thus influence the crystallization and quality of the final MHP layer.…”

Electrohydrodynamically Printed High‐Resolution Full‐Color Hybrid Perovskites

“…For the eventual application in display, full color and capability of patterning are compulsory, while high resolution is strongly preferred. To meet this requirement, the current state‐of‐the‐art patterning strategy for perovskite is inkjet printing, which has been widely used to pattern quantum dots and organic materials . This strategy is however restricted by the relative coarse resolution over 50 µm, failing to meet the requirement for high‐resolution display applications .…”