Digital Light Processing of Ligand-Engineered FAPbBr ₃ Composites for 3D Luminescent Structures with Geometry-Dependent Optical Properties

Halide perovskites exhibit remarkable photoluminescence; however, it is difficult to process them into robust three-dimensional (3D) devices because of their instability and poor compatibility with photocurable polymers. In this study, a digital light processing (DLP) additive manufacturing strategy was developed to overcome these limitations by combining surface-engineered formamidinium lead bromide (FAPbBr 3 ) with photopolymerizable resins. Initially, commercially available FAPbBr 3 particles were capped with oleic acid and oleylamine to improve their dispersibility and interfacial compatibility with an acrylate matrix, thereby enabling rapid cross-linking and homogeneous curing during DLP printing. Using this resin, centimeter-scale 3D structures including free-form lattices, representative text, logo-like, and QR-code-like patterns were printed with clear pattern definition, bright cyan-green emission under ultraviolet illumination, and good mechanical integrity. Photoluminescence imaging and color coordinate analysis confirmed that the emission characteristics of FAPbBr 3 were preserved throughout the printing process, and microscopic examination revealed an accurate reproduction of the fine pattern details. Moreover, substituting the perovskite with MAPbI 3 or CsPbBr 3 produced red- and blue-emitting structures, demonstrating the versatility of this method for multicolor printing. Overall, these results indicate that DLP printing of ligand-engineered perovskite composites enables the fabrication of stable luminescent 3D structures on practical scales, thereby opening avenues for optical displays, information encoding, security marking, and other functional photonic applications.