Micro- and Nanostructured Lead Halide Perovskites: From Materials to Integrations and Devices

In the past decade, lead halide perovskites have been intensively explored due to their promising future in photovoltaics. Owing to their remarkable material properties such as solution processability, nice defect tolerance, broad bandgap tunability, high quantum yields, large refractive index, and strong nonlinear effects, this family of materials has also shown advantages in many other optoelectronic devices including microlasers, photodetectors, waveguides, and metasurfaces. Very recently, the stability of perovskite devices has been improved with the optimization of synthesis methods and device architectures. It is widely accepted that it is the time to integrate all the perovskite devices into a real system. However, for integrated photonic circuits, the shapes and distributions of chemically synthesized perovskites are quite random and not suitable for integration. Consequently, controlled synthesis and the top-down fabrication process are highly desirable to break the barriers. Herein, the developments of patterning and integration techniques for halide perovskites, as well as the structure/function relationships, are systematically reviewed. The recent progress in the study of optical responses originating from nanostructured perovskites is also presented. Lastly, the challenges and perspective for nanostructured-perovskite devices are discussed.