Structural and Physical Properties of Two Distinct Two-Dimensional Lead Halides with Intercalated Cu(II): A Comparative Study

Transition metal cations intercalated between the two-dimensional (2D) layers of metal halides is a new and distinct category of the metal halides family. In this work we focus the synthesis and property characterizations of two layered hybrid lead halides: <b>(1)</b> a new compound [Cu(O₂C-CH₂-NH₂)₂]Pb₂Br₄ and <b>(2)</b> the reported [Cu(O₂C-(CH₂)₃-NH₃)₂]PbBr₄. These compounds have a 2D layered structure with the intercalated Cu²⁺ metals between the layers, achieved by combining metal halides with zwitterionic amino acids. The incorporation of metal organic cluster consisting of zwitterions and transition metal cation as an interlayer result in improvement of electronic charge transport properties between the layers. Physical properties like magnetization measurements and thermal conductivity have also been studied for both compounds. To gain more insights into their structural and chemical diversity, we explored the solution chemistry for the synthesis of the titled compounds. The fingerprints of formed metal-halide complexes in solution were confirmed by UV−Vis spectroscopy and small-angle X-ray scattering (SAXS) experimental techniques combined with density functional theory (DFT) calculations. Moreover compound (1) showed anisotropic charge transport properties with a good and different semiconductor resistivity measured along the a-axis and along the bc plane, respectively. The fabricated prototype detector showed response to soft low-energy X-rays at 8 keV with a detector sensitivity of 1462.7 uCGy^-1cm^-2, indicating its potential application for ionizing radiation detection.