Realizing CsPbBr₃ Light-Emitting Diode Arrays Based on PDMS Template Confined Solution Growth of Single-Crystalline Perovskite

Metal-halide perovskites have shown excellent optoelectronic properties, among which the array-type architecture is highly desirable. However, both the susceptibility of perovskites to polar solvents and the complex 3D geometry of array structure have led to great challenges for device fabrication and performance, which hinders their further applications. Here, we report a simple but efficient approach highly compatible with the state-of-the-art microelectronics processes to construct single-crystalline array light-emitting diodes (LEDs) of perovskite. The well-aligned single-crystalline array was sandwiched as the emission layer, among the carefully designed multilayer ITO/NiO/CsPbBr3/PMMA/ZnO/Ag structure. Through systematically altering the size of CsPbBr3 single crystal and the thickness of insulation layer, the device performance has been optimized and eventually achieved a 99% working ratio in a 62 x 47 array. Moreover, a prototype device of LED display was also fabricated. These results clearly demonstrate that our strategy is efficient, reliable, and versatile, which can be easily extended to other perovskites.