One-dimensional halide perovskite single crystals for optoelectronic applications

Metal halide perovskites have recently begun to flourish in the field of optoelectronics. However, the inherent instability and grain boundary defects of traditional three-dimensional (3D) and two-dimensional (2D) polycrystalline films remain significant obstacles hindering their commercialization. Consequently, one-dimensional (1D) halide perovskite single crystals (PSCs) have garnered considerable attention due to their unique “molecular wire” structures. This distinctive structural constraint endows 1D PSCs with exceptional physical properties: strong quantum and dielectric confinement effects, broadband emission driven by self-trapped excitons, significant optoelectronic anisotropy, and excellent environmental stability. This article reviews the recent advances in 1D halide PSCs. We systematically explore the fundamental crystal structures and their derived photophysical properties, with a focus on elucidating the mechanisms behind their high quantum yields and nonlinear optical responses. Furthermore, various single-crystal growth strategies, ranging from slow cooling crystallization and inverse temperature crystallization to space-confined synthesis, are critically analyzed. Finally, we summarize the cutting-edge applications of 1D PSCs in high-performance UV–vis photodetectors, x-ray detectors, light-emitting diodes, and emerging polarization-sensitive devices.