A screening of the reactions between BiI₃ and iodide salts of different N-alkylated heterocycles (pyridine, quinoline, isoquinoline) resulted in the preparation and structural characterization of six novel iodobismuthate complexes, including two compounds exhibiting an unprecedented {[Bi₃I₁₀]} polymeric moiety. It has been shown that the chemical composition and structure of the iodobismuthates significantly affect their optical and electronic properties. In particular, the narrowest band gaps (E_g) were revealed by {[Bi₃I₁₀]} iodobismuthates, while the compounds incorporating {[BiI₄]} polymeric frameworks showed 0.2–0.3 eV wider E_g. GIXRD analysis evidenced that all three iodobismuthates investigated in thin films show mainly the horizontal (parallel to the substrate) orientation of the 1D polymeric Bi–I frameworks. Such arrangement blocks the charge transport in vertical direction (orthogonal to the substrate) since the conductive Bi–I chains are separated with insulating bulky organic cations. As a consequence, standard planar junction solar cells based on new iodobismuthates revealed low power conversion efficiencies approaching 0.12% only. However, strong in-plane photoconductivity observed for iodobismuthates enabled the fabrication of efficient planar photodetectors, which paves a way to the practical use of this exotic family of materials. Most importantly, the presented systematic study revealed the most general guidelines for future rational design of perovskite-like materials for emerging generation of environment-friendly perovskite photovoltaics emphasizing the importance of the isotropic charge transport in the films of 3D materials and achieving proper orientation of 1D and 2D frameworks with respect to the charge collecting electrodes in anisotropic low dimensional systems.

Terbium oxide films have been grown on Si(111) substrates by decomposition of Tb(dpm)₃ vapor in argon flow at Tb(dpm)₃ source temperatures of 170 and 190°C and substrate temperatures from 470 to 550°C. The films have been annealed in air at temperatures of 400, 650, and 800°C. X-ray diffraction characterization results show that the films grown by chemical vapor deposition consist of cubic Tb₂O₃. The films annealed in air at 650 and 800°C are isostructural with Tb₄O₇, and those annealed at 400°C are isostructural with Tb₁₁O₂₀. According to X-ray photoelectron spectroscopy data, the 9-nm-thick surface layer of the Tb₂O₃ film has the correct stoichiometry O: Tb = 1.48, whereas the film annealed at 800°C has O: Tb = 1.85. Raman spectroscopy data demonstrate that the concentration of carbon-containing species on the surface of the films decreases with decreasing substrate temperature and can be brought to zero by air annealing at 800°C.