Three new lead iodide chain compounds, APbI3, templated by molecular cations

Abstract

The crystal structures of three new hybrid organic-inorganic lead halide compounds [IqH]PbI3, [4MiH]PbI3, and [BzH]PbI3 ([IqH+] = isoquinolinium, [4MiH+] = 4-methylimidazolium, [BzH+] = benzotriazolium) have been determined by single crystal x-ray diffraction. All three compounds have the same generic formula as perovskite, ABX3, but adopt a rare non-perovskite structure built from one dimensional (1D) edge-sharing octahedral chains. The bandgap of each compound was investigated by solid UV-Vis spectra. In comparison with previously reported hybrid compounds containing the same type of octahedral chains, [C10H7CH2NH3]Pbl3 and (C7H7N2)PbI3, all three new compounds have lower bandgaps (<2.4 ev), indicating that they may be promising for photovoltaic application.