A New Inorganic-organic Hybrid Based on Biisoquinoline and Hexachloridostannate:Structure, Photoluminescence, Electrochemical Behavior and Theoretical Study

A new inorganic-organic hybrid constructed from biisoquinoline dication and tin halide, [（BIQBT）（Sn Cl6）]n（1, BIQBT = 1,4-bis（isoquinoline） butane）, has been synthesized and structurally determined by X-ray diffraction method. 1 crystallizes in the monoclinic system, space group Cc with Mr = 644.82, a = 16.589（3）, b = 18.388（4）, c = 8.5532（17）A, β = 108.75（3）°, V = 2470.6（9） A3, Z = 4, Dc = 1.736 g/cm^3, F（000） = 1281, μ（Mo Kα） = 1.697 mm^–1, the final R = 0.0197 and wR = 0.0493 for 4614 observed reflections with I 〉 2（I）. 1 consists of BIQBT^2＋dications and mononuclear hexachloridostannate Sn Cl62- anion, and hydrogen bonds among them contribute to the formation of a 1-D chain. Strong fluorescence can be detected in 1, which was explained by theoretical calculation. Its electrochemical behavior was investigated, and the theoretical calculations reveal that the π···π stacking interaction is dominated for their structural stabilization.

A New Bismuth(Ⅲ) Iodide Inorganic/organic Hybrid Solid Containing Large Heterocyclic Conjugated Organic Ligand: Synthesis, Properties and Calculations

A new bismuth（III） iodide inorganic/organic hybrid containing larger heterocyclic conjugated organic ligand, [（dppz）2Bi2I6]·2DMF （1） （dppz = dipyrido[3,2-a：2＇,3＇-c]phenazine）, has been synthesized by solution process and structurally determined by X-ray diffraction method. 1 crystallizes in triclinic, space group Pī with Mr= 1844.08, α = 9.215（5）, b = 11.488（6）, c = 12.424（9） ？, α = 106.66（2）, β = 90.84（2）, γ = 92.34（2）°, V = 1258.5（13） ？3, Z = 1, Dc = 2.433 g/cm3, F（000） = 830, μ（MoKα） = 10.702 mm–1, the final R = 0.0834 and wR = 0.1947 for 2749 observed reflections with I 〉 2σ（I）. 1 consists of a dimeric structure [（dppz）2Bi2I6], in which two [（dppz）BiI3] fragments are bridged by a pair of iodine atoms. Hydrogen bonds and π···π stacking interactions contribute to the structural extension and stabilization. Experimental band gap of about 2.13 eV indicates its semiconductor nature. The optical absorption spectrum and electronic structure were also discussed.

Double Free:A Promising Route toward Moisture-Stable Hypotoxic Hybrid Perovskites

The moisture instability and toxicity of lead have hindered the development of lead organometal halide perovskites(Pb-OHPs).Similar to Pb-OHPs,OHPs based on Pb-free elements,including Group VA metals Bi and Sb(denoted as M),exhibit optoelectronic properties due to their isoelectronic configuration and close chemistry of the lone-pair ns^(2) state.However,M-OHPs are mostly based on hydrophilic protonated organic countercations and possess low structural dimensionalities,which affect the moisture stability and disrupt continuous carrier transport,respectively.Herein,we demonstrate a“double-free”strategy to realize the rational synthesis of moisture-stable hypotoxic hybrid perovskites.A hydrogen-bond-free alkylated countercation was assembled with Pb-free OHP bearing an extended structure in one molecule.As a proof of concept,two double-free M-OHPs are synthesized,which show greatly improved moisture and photostability compared to their corresponding hydrogen-bond OHPs and the extensively studied MA_(3)M_(2)X_(9)(MA=CH_(3)NH_(3)^(+)).The photoconduction behaviors of both double-free OHPs display short rise and decay recovery time and exhibit excellent photocurrent reproducibility.Importantly,(1-methyl-4-phenylpyridin-1-ium)BiI_(4)(Me4ppi-BiI_(4))displays a comparable switching on/off ratio with MA_(3)Bi_(2)I_(9),and can endure 75% relative humidity(RH)for at least 243 days.The photophysical property measurements and theoretical calculations show that this remarkable photoconversion performance results from the relatively low exciton binding energy and greatly improved carrier mobility and concentration.

Syntheses and Characterizations of(CH_3CH_2CH_2CH_2NH_3)_6(BiI_6)(I)_2I_3 and (NH_3CH_2CH_2NH_3)_2Bi_2I_(10)

The title compounds have been respectively synthesized by solution process and solvothermal reaction, and their crystal structures were determined by X-ray diffraction method. For （CH3CH2CH2CH2NH3）6（BiI6）（I）2I3 1, it crystallizes in tficlinic, space group P1^- with Mr = 2049.76, a = 8.5719（1）, b = 11.7461（3）, c = 15.700（1）A, V = 1451.4（1）A^3, Z = 1, Dc = 2.345 g/cm^3, F（000） = 924, μ（MoKα） = 8.907 mm^-1, T = 293（2） K, the final R = 0.0655 and wR = 0.0804 for 2399 observed reflections with I 〉 2σ（I）. For （NH3CH2CH2NH3）2Bi2I10 2, it crystallizes in monoclinic, space group P21/n with Mr= 1811.20, a = 8.434（4）, b = 13.862（6）, c = 13.362（6）A, V = 1499.9（12）A^3, Z = 2, Dc = 4.010 g/cm^3, F（000） = 1536,μ（MoKα） = 22.007 mm^-1, T = 293（2） K, the final R = 0.0584 and wR = 0.1451 for 1798 observed reflections with I 〉 2σ（I）. The structures of 1 and 2 contain halobismuthate monomer and dimers, respectively. It is noteworthy that the dimers and their organic counters in 2 connect each other by N…I hydrogen bonds to form a layered structure, and the electrostatic interactions and crystal packing forces between layers give rise to the packing of the crystal. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.13 and 2.01 eV, respectively.

Synthesis and Characterization of [NH_3(CH_2)_2NH_2(CH_2)_2NH_3]BiCl_6

The title compound （[NH3（CH2）2NH2（CH2）2NH3]BiCl6, Mr= 527.88） has been synthesized by diffusion method and its crystal structure was determined by X-ray diffraction method. It crystallizes in orthorhombic, space group P212121 with a = 6.8444（4）, b = 13.6329（10）, c = 15.6641（12）A°, V= 1461.60（18）A°^3, Z= 4, Dc = 2.399 g/cm^3, F（000） = 984,μ（MoKα） = 13.132 mm^-1 and T = 293（2） K. The final R = 0.0294 and wR = 0.0490 for 2325 observed reflections with I 〉 2σ（I）. Each bismuth atom in the present compound is coordinated by six chlorine atoms to furnish a slightly distorted octahedral geometry. It is worthy to note that each adjacent [BiCl6]^3- and [H3dien]^3＋ entities are linked by hydrogen bonds to form two right- and left-handed helical double-chains running along the b axis. These two helical double-chains are interlaced into quadruple-stranded braid to give rise to a three- dimensional network. The optical absorption spectrum of the compound reveals the appearance of a sharp optical gap of 3.30 eV.