As a new type of semiconductor material, metal halide perovskite (MHP) has shown great application potential in many fields, such as solar cells, light-emitting diodes (LEDs), photodetectors, X-ray detectors, and lasing devices. In particular, since Miyasaka et al. first employed three-dimensional (3D) MAPbI3 in photovoltaics (PVs) in 2009, the certified power conversion efficiencies (PCEs) of the perovskite PV devices have been improved from 3.8% to 25.2% today. This is mainly due to their advantageous physical properties, such as high light absorption coefficient, slow charge carrier recombination rate, and high carrier mobility. However, 3D MHPs are very sensitive to moisture and temperature, etc., which hindered their commercialization. In this case, more and more researchers set their sights on more stable low-dimensional MHPs, such as 2D layered, 1D linear, and 0D punctuated MHPs.
In this thesis, we developed the MHP crystals with molecular dimensionality from 3D, 2D to 0D, analyzed their structures and investigated their photophysical properties. We tried to correlate those intrinsic features with their structural characteristics. In addition, we achieved some prototype photodetector devices based on those MHP materials with enhanced performance after structural engineering. Our results revealed the entirely different critical structural factors that dominate the optical features of the MHPs with various dimensionality.