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81.
Yue Liu Yuxiang Wang Haoran Cheng Dr. Zheng Ma Dr. Qian Li Prof. Gang Wang Prof. Daocheng Pan Prof. Limin Wang Prof. Jun Ming 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(25):e202104463
Inorganic cesium lead halide perovskite nanocrystals are candidates for lighting and display materials due to their outstanding optoelectronic properties. However, the dissolution issue of perovskite nanocrystals in polar solvents remains a challenge for practical applications. Herein, we present a newly designed one-step spin-coating strategy to prepare a novel multicolor-tunable CsPbX3 (X=Cl, Br, I) nanocrystal film, where the CsPbX3 precursor solution was formed by dissolving PbO, Cs2CO3, and CH3NH3X into the ionic liquid n-butylammonium butyrate. The as-designed CsPbX3 nanocrystal films show high color purity with a narrow emission width. Also, the blue CsPb(Cl/Br)3 film demonstrates an absolute photoluminescence quantum yields (PLQY) of 15.6 %, which is higher than 11.7 % of green CsPbBr3 and 8.3 % of red CsPb(Br/I)3 film. This study develops an effective approach to preparing CsPbX3 nanocrystal thin films, opening a new avenue to design perovskite nanocrystals-based devices for lighting and display applications. 相似文献
82.
83.
Matthew?W.?Dodge William?F.?WacholtzEmail author Joel?T.?Mague 《Journal of chemical crystallography》2005,35(1):5-12
Tris-(-(3-methyl-5-trifluoromethylpyrazolato)-N:N)triangulo-trigold(I), (3,5-tfmpz)3 Au3, has been synthesized and exhibits a planar nine-member ring containing a central gold triangle with an average intramolecular Au–Au distance of 3.3455(8) Å. The complex crystallizes in the monoclinic space group Cc with a = 12.998(2) Å, b = 22.910 (3) Å, c = 7.217(1) Å, and = 104.781(1). The solid-state structure consists of sheets of (3,5-tfmpz)3Au3 units stacked in an offset fashion along the c axis such that one gold atom in each Au3 unit (Au1) lies approximately over the midpoint of the Au1–Au3 edge of the triangle in the layer below it. The intermolecular Au–Au distances are between 3.880(1) and 4.023(1) Å, which are too long for there to be significant intertrimer bonding interaction suggesting that any supramolecular organization may be due to hydrogen-fluorine and fluorine-fluorine interactions between the molecules. The complex exhibits excitation-dependent emission at room temperature in the solid state. The structured higher energy emission (em = 468, 517, and 556(sh) nm) is believed to be a ligand-centered * transition with a lower energy unstructured emission (em = 658 nm) assigned to the classical Au–Au excited state transition. 相似文献
84.
The title compound [Zn(btzb)2Cl2]·2H2O (1·2H2O, btzb = 1,2-bis(5-tetrazolyl)ben- zene) was synthesized in situ by the [2+3] cycloaddition reaction of phthalonitrile with NaN3 in water in the presence of ZnCl2 under refluxing conditions. 1·2H2O crystallizes in the monoclinic system, space group P2 1/c with a = 9.0119(18), b = 7.5566(15), c = 18.076(5)A, β= 114.67(2)°, V= 1118.6(4)A^3, Z = 2, Dc = 1.784 g/cm^3, T= 223(2) K, C16H16N16O2Cl2Zn, Mr = 600.74, F(000) = 608, μ(MoKα) = 1.393 mm^-1, S = 1.081, R = 0.0306 and wR = 0.0669 for 1896 observed reflections with I 〉 2σ(I). The Zn^2+ ion of 1 is coordinated by four N atoms from two btzb ligands and two Cl atoms, forming a distorted octahedral coordination geometry. A number of intermolecular hydrogen bon- ding interactions between molecules 1 and/or the solvated water molecules result in a 3D hydrogen-bonded structure. The luminescent property of 1·2H2O was also investigated. 相似文献
85.
Lanthanide luminescent materials play key roles in modern society, but their first-principles treatment remains a great challenge due to complex manifold of electronic excited states and the difficulty in performing excited state structural relaxations that is necessary to model luminescent properties. Herein, we propose a practical approach that combines embedded cluster model (ECM) based multi-configurational wave function theory (WFT) and occupancy constrained density-functional theory plus the Hubbard U correction (OC-DFT + U) to treat lanthanide doped luminescent materials, using LaF3:Ce3+, a typical scintillator with low symmetry, as a case study. We show that the combined approach yields accurate absorption energies with an error on the order of 200 cm−1, but the emission energies are significantly underestimated, the origin of which is further clarified by vibrationally resolved absorption and emission spectra calculation. This work demonstrates the possibility of combining ECM-based wave function theory and periodic DFT into a comprehensive computational scheme for lanthanide luminescent materials and highlights the limitations of the current implementation of OC-DFT + U for excited state structural optimization. 相似文献
86.
《Mendeleev Communications》2023,33(1):130-132
A glass with CdS nanoparticles was used simultaneously as a matrix for Ce-doped garnet and a yellow-red phosphor to prepare luminescent glass ceramics for the sources of white light. CdS nanoparticles compensate for the unbalanced Ce3+ emission spectrum of the composite material due to the addition of a red component. The synthesized composite material can be a tunable light converter due to altered luminescence spectra by changing the sintering conditions and excitation wavelength 相似文献
87.
共轭聚合物发光和光伏材料研究进展 总被引:5,自引:1,他引:4
聚合物光电功能材料与器件因其广阔的应用前景,1990年以年来吸引了世界各国学术界的广泛关注和兴趣.聚合物光电子器件主要包括聚合物电致发光二极管、聚合物场效应晶体管和聚合物太阳能电池等,其使用的关键材料是共轭聚合物光电子材料,包括共轭聚合物发光材料、场效应晶体管材料和光伏材料等.本文主要对共轭聚合物电致发光材料和光伏材料的研究进展进行综述,介绍了这些聚合物材料的种类、结构和性质以及在聚合物电致发光器件和聚合物太阳能电池中的应用.并讨论了当前共轭聚合物光电子材料中的关键科学问题和今后的发展方向. 相似文献
88.
Dr. Aline Varella Rodrigues Bruno Seiki Domingos Onishi Prof. Dr. Sidney José Lima Ribeiro 《Chemphyschem》2023,24(21):e202300134
This research endeavors to overcome the significant challenge of developing materials that simultaneously possess photostability and photosensitivity to UV-visible irradiation. Sulfurized nanorod (NR)-like ZnO/Zn(OH)2 and hierarchical flower-like γ-Zn(OH)2/ϵ-Zn(OH)2 were identified from XRD diffraction patterns and Raman vibrational modes. The sulfurized material, observed by FEG-SEM and TEM, showed diameters ranging from 10 and 40 nm and lengths exceeding 200 nm. The S2− ions intercalated Zn2+, modulating NRs to dumbbell-like microrods. SAED and HRTEM illustrated the atomic structure in (101) crystal plane. Its direct band gap of 3.0 eV was attributed to the oxygen vacancies, which also contribute to the deep-level emissions at 422 and 485 nm. BET indicated specific surface area of 4.4 m2 g−1 and pore size as mesoporosity, which are higher compared to the non-sulfurized analogue. These findings were consistent with the observed photocurrent, photostability and photoluminescence (PL), further supporting the suitability of sulfurized NR-like ZnO/Zn(OH)2 as a promising candidate for Luminescent solar concentrators (LSC)-photovoltaic (PV) system. 相似文献
89.
Uninuclear europium (Eu), as well as binuclear Eu and terbium (Tb), complexes were synthesized using acrylic acid (AA) as the first ligand and 1,10-phenanthroline (Phen) as the second ligand. The relative weight ratio of the europium (III) (Eu3+) to terbium (III) (Tb3+) ions of the binuclear complex was 1:1 as determined via energy dispersive X-ray analysis. The structures of the Eu(AA)3Phen and Eu0.5Tb0.5(AA)3Phen complexes were characterized by Fourier transform infrared spectroscopy. A series of tri-cellulose acetate (TCA)/ the Eu(AA)3Phen and TCA/Eu0.5Tb0.5(AA)3Phen composites were prepared by solution blending, and their luminescent properties were investigated by fluorescence spectrophotometry. The excitation spectra of all composites indicated that the TCA matrix probably affected the energy absorption and transfer of organic ligands. In TCA/Eu0.5Tb0.5(AA)3Phen composites the introduced Tb3+ ions had some influence on energy absorption and transfer of organic ligands; the energy transfer process of the complex is suggested to be as follows: Phen→AA→Tb3+ion→Eu3+ion. The emission spectra indicated that the luminescent intensity of the TCA/Eu0.5Tb0.5(AA)3Phen composites was noticeably stronger than that of the TCA/Eu(AA)3Phen composites, suggesting that the comparatively stable and high-efficiency energy transfer process was only slightly influenced by the TCA matrix. In summary, the TCA/Eu0.5Tb0.5(AA)3Phen (90/10) composite possesses fine luminescent properties for potential usage as red fluorescent materials. 相似文献
90.
Four coordination polymers based on 4′-(2H-tetrazol-5-yl)biphenyl-4-carboxylic acid (H2TBPC), [Zn(μ3-TBPC)(H2O)]n (1), [Zn(μ3-TBPC)(Me2NH)]n (2), [Cd(μ3-TBPC)(bpy)]n (bpy = 4,4′-bipyridine, 3), and [Cd(μ4-TBPC)(H2O)]n (4), were constructed under hydrothermal conditions. The compounds are composed of M2(TBPC)2 binuclear ring as a building block. In 1–3, the binuclear rings are interconnected to three different 2-D networks with the same (4·82) topology. In 4, the binuclear rings are arranged into a 3-D framework with PtS-type topology. The results revealed that the structural diversity is mainly attributed to the coordination geometries of metal ion, the coordination modes of TBPC2?, and the auxiliary ligand. The thermal stabilities and luminescent properties of 1–4 have also been studied. 相似文献