High stability and moderate second-order nonlinear optical properties of hybrid lead-free perovskite [(CH3)3NCH2Cl]CdCl3 bulk crystals†
Abstract
By combining stereochemically active lone-pair d10 metal Cd2+ with halogen anions was identified as an effective method to obtain enhanced nonlinear optical (NLO) materials. In this work, hybrid lead-free perovskite [Me3NCH2Cl]CdCl3 (abbreviated as (TMCM)CdCl3) bulk crystals were grown by the solution method, which demonstrates the one-dimensional chainlike perovskite structure with distorted {CdCl6} irregular octahedrons. The environmental, temperature, and atmospheric stabilities were systematically evaluated with a reversible transition and the phase decomposition point were determined at 125 and 271 °C, respectively. In addition, high environmental and high solvent atmospheric stability were also detected. A wide transparent region (200–900 nm) and wide band gap of 5.24 eV were determined with a moderate second harmonic generation (SHG) response of 0.73 times that of KH2PO4. Furthermore, theoretical calculations were performed to investigate the relationship between structure and performance, and an applicable birefringence of 0.043 was calculated at 1064 nm. All the results make (TMCM)CdCl3 a promising candidate for NLO material, which may also have potential applications in the solar-blind UV region.