Metal halide perovskites have been widely studied due to their excellent optoelectronic properties and has been used as light emitting diodes, photodetectors, PV devices and other light harvesting applications. The ease of processing and a structure that can be tuned makes halide perovskites a suitable candidate for a variety of optical and electronic applications. Halide perovskites have a unique structural tunability where the small inorganic/organic cation can be replaced by a larger organic cation to make low dimensional perovskites such as 2D, 1D and 0D. So, the selection of organic cations, metals and halogens play a very crucial role in deciding the moiety of the materials and tune their optoelectronic properties.
In this work, we propose a selective way to tailor the dimensionality of Cs2AgBiBr6 3D semiconductor into 2D (BA4AgBiBr8), 1D (BZA3BiCl5.Cl.H2O) and 0D (BZA3BiBr6, BZA3BiI6) network by introducing the aliphatic/aromatic cations (butylammonium and benzylammonium) between the inorganic sheets and varying the halogen (chlorine, bromine and iodine) in the octahedra of the inorganic sheets. We have also tried to introduce the non-centrosymmetric behaviour in A’4AgBiBr8 2D perovskite material by selectively halogenating the organic A’ site cation (3-bromopropylammonium; 3-BPA and 3-chloropropylammonium, 3-CPA). The crystal structures of these materials were solved and their structural properties and dimensionality have been investigated. The systematic distortion in these materials were studied in detail using the combination of single crystal XRD, Raman and FT-far-IR spectroscopies. We observed the substantial role of dimensionality on the morphological, thermal, optical absorption and light emitting properties.