The Chemistry of Tin Halide Perovskite Nanocrystals

<br/> Metal halides perovskites with nanoscale geometries have revolutionized the field of solution-processed photovoltaics and light-emitting devices due to their strong absorption and exceptional photoluminescence properties combined with a remarkable tolerance to structural defects. However, the further development of these materials to practical commercialization is hindered by their toxic components like lead and their inherent structural lability. Moreover, we still have little understanding of their crystallographic structures, chemical and physical interactions, and surface chemistry at a fundamental level.<br/> <br/>The chemical design of metal halide perovskites proved to be the key to addressing those issues. In this work, I will discuss the physical and chemical parameters which can help us to achieve a stable, tunable and monodisperse CsSnX₃ perovskite nanocrystals with defined optical features. Pertaining to the formation energies of nanostructures, the interplay of the 2D Ruddlesden-Popper (L₂Cs_n-1Sn_nX_3n+1) phases with 3D CsSnX₃ nanocrystals is apparent with respect to ligand combinations (ammonium, carboxylate, phosphinate), precursor ratios and temperature when SnX₂ salt is used as a precursor. X-ray diffraction and scattering studies conjoined with optical spectroscopy and electron microscopy helps us in acquiring the useful insights into directing the chemistry of Sn-halide perovskites at nanoscale. This research work showcases the insistent necessity for the development of mechanistic understanding to design efficient synthetic routes to achieve high-quality tin-halide perovskite nanocrystals.