查看文章

Lead halide perovskites show enormous potential for display because of their tunable emission, high color purity, strong photoluminescence and electroluminescence. However, it is a huge challenge to achieve high resolution patterning with perfect crystalline morphologies of perovskite crystals. In this work, we combine a high-viscosity perovskite precursor with polyvinylpyrrolidone (PVP) and powerful electrohydrodynamic (EHD) printing to fabricate in situ crystallized high-resolution microarrays with perfect morphologies. Adding PVP contributes to reducing capillary flow to eliminate coffee rings and form spatial confinement during evaporation, limiting the flow of ions and the size of perovskite grains. However, it increases the solution viscosity, which makes printing rather difficult. This problem is solved by introducing EHD printing, which has superior advantages in high-viscosity ink printing and high-resolution …