Single crystal, a lead-free hybrid organic-inorganic perovskite material: {[(C6H5)NH3]+}4.I.[BiI6]3-.H2O with optical and third-order nonlinear properties

Abstract

A lead-free organic–inorganic halide perovskite (LFHP) single crystal, tetrakis(phenylammonium) iodide hexaiodidebismuthate monohydrate (TIHM): {[(C6H5)NH3]+}4.I.[BiI6]3-.H2O, was successfully synthesized by a simple condensation reaction method in ambient environment. The bismuth iodide-based crystal compound was grown by using methanol solvent. The crystal lattice comprised of a discrete (BiI6)3− anion surrounded by tetrakis(phenylammonium) cations, iodide anion, and a water molecule. The structure related to monoclinic crystal system with P21/c space group: a ​= ​21.921 (4) Å, b ​= ​8.5521 (15) Å, c ​= ​21.105 (4) Å, β ​= ​102.398 (3) °, and Z ​= ​4. The full geometry optimization was performed by density functional theory (DFT) calculation at B3LYP functional with 6–311++G(d,p) and LanL2DZ mixed basis sets by using GAUSSIAN software. The gaussian predicted peak emission at 479 ​nm with bandgap of 2.97 ​eV. The HRTEM analysis reveals that the titled LFHP nanocrystal has a size below 5 ​nm. The centrosymmetric crystal exhibit third-order nonlinear optical susceptibility of 1.0228 ​× ​10-5 ​esu with Im χ3 response higher than Reχ3, and, hence, it can be concluded that the hybrid perovskite has promising optical limiting properties.