Achieving a balance between high selectivity and uptake is a formidable challenge for the purification of acetylene from mixtures with carbon dioxide, particularly when seeking to maximize both CH adsorption capacity and CH/CO separation selectivity in crystalline porous materials. In this study, leveraging the principles of reticular chemistry, we selected two tetracarboxylate-based linkers and combined them with Cu ions to synthesize two isoreticular dicopper paddle-wheel-based metal-organic frameworks (MOFs): Cu-TPTC (terphenyl-3,3',5,5'-tetracarboxylic acid, HTPTC) and Cu-ABTC (3,3,5,5-azobenzenetetracarboxylic acid, HABTC). The structural and sorption analyses revealed that Cu-ABTC, despite having slightly smaller pores due to the strategic replacement of a phenyl ring with an azo group between two tetratopic ligands, maintains high porosity compared to Cu-TPTC.
View Article and Find Full Text PDFThe efficient single-step purification of ethylene from ternary C mixtures containing ethane and acetylene is challenging and demanding. Herein, we introduce a novel cerium-based metal-organic framework (MOF) of Ce-NTB- synthesized via a ligand-conformer strategy. The Ce-NTB- features a rare tetranuclear cerium cluster and 2D layers pillared by a 3D framework concomitant with an extraordinary (3,3,12)-c network.
View Article and Find Full Text PDFDue to their intrinsic structural features, the design and synthesis of a new type of zeolite-like metal-organic frameworks (ZMOFs) is highly desirable but challenging. Herein, solvothermal reactions between an angular dicarboxylate linker and rare-earth (RE) ions afforded two RE-MOFs, namely, Tb-ZMOF-2 and Tb-ZMOF-3, respectively. Structural analyses reveal that Tb-ZMOF-2 encompasses a novel [468] cage, while Tb-ZMOF-3 contains nonanuclear (i.
View Article and Find Full Text PDFRecently, inorganic halide perovskite (CsPbX3, X = Cl, Br, I) quantum dots (QDs) have attracted tremendous research interests because of their great potential for application in the fields of low-cost light sources and displays. However, the unsatisfactory structural and chemical stabilities of such materials are the main obstacles hindering reliable device operation significantly. In this study, we successfully prepared CsPbBr3/silica QD composites through a simple sol-gel reaction by using tetramethoxysilane as a single molecule precursor.
View Article and Find Full Text PDFSemi-transparent all-oxide light-emitting diodes based on ZnO/NiO-core/shell nanowire structures were prepared on double-polished c-Al2O3 substrates. The entire heterojunction diode showed an average transparency of ∼65% in the ultraviolet and visible regions. Under forward bias, the diode displayed an intense ultraviolet emission at ∼382 nm, and its electroluminescence performance was remarkable in terms of a low emission onset, acceptable operating stability, and the ability to optically excite emissive semiconductor nanoparticle chromophores.
View Article and Find Full Text PDFUnlabelled: Recently, perovskite-based light-emitting diodes based on organometal halide emitters have attracted much attention because of their excellent properties of high color purity, tunable emission wavelength and a low-temperature processing technique. As is well-known, organic light-emitting diodes have shown powerful capabilities in this field; however, the fabrication of these devices typically relies on high-temperature and high-vacuum processes, which increases the final cost of the product and renders them uneconomical for use in large-area displays. Organic/inorganic hybrid halide perovskites match with these material requirements, as it is possible to prepare such materials with high crystallinity through solution processing at low temperature.
View Article and Find Full Text PDFUnlabelled: Direct fabrication of semiconductor light emitting devices on metal foils is beneficial, because it brings flexibility and good heat sink in the devices. In this work, we have grown ZnO on the commercially available stainless steel foils by metal-organic chemical vapor deposition for the first time. With the increase of growth temperature, the morphology changes from a thin film structure to closely stacked columns, and eventually to nanorods.
View Article and Find Full Text PDFVertically aligned ZnO/MgO coaxial nanowire (NW) arrays were prepared on sapphire substrates by metal-organic chemical vapor deposition combined with a sputtering system. We present a comparative investigation of the morphological and optical properties of the produced heterostructures with different MgO layer thicknesses. Photoluminescence measurements showed that the optical performances of ZnO/MgO coaxial NWs were strongly dependent on the MgO layer thickness.
View Article and Find Full Text PDFElectrically pumped lasing action has been realized in ZnO from an n-MgZnO/i-ZnO/SiO2/p-Si asymmetric double heterostructure, an ultralow threshold of 3.9 mA was obtained. The mechanism of the laser is associated with the in-plane random resonator cavities formed in the ZnO films and the elaborate hollow-shaped SiO2 cladding pattern, which prevent the lateral diffusion of injection current and ultimately lower the threshold current of the laser diode.
View Article and Find Full Text PDFIn the present paper, the authors study the photolumimescence spectra of the novel 2,3-tetra-(2-isopropyl-5-methylbenzoyl) hydrogen phthalocyanine casting film and vacuum-deposited film. Photolumimescence spectras of casting film on the quartz substrate were measured at 10, 77, 177 and 300 K, and the photolumimescence spectra of vacuum-deposited film with a thickness of about 200 nm on the silicon substrate was studied at room temperature (300 K). For 2,3-tetra-(2-isopropyl-5-methylbenzoyl) hydrogen phthalocyanine, the casting films all show fluorescence peaks at 942, 937, 942 and 942 nm and phosphorescence peaks at 1114, 1057, 1114 and 1114 nm in the photolumimescence spectra at 10, 77, 177 and 300 K, respectively.
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