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Abstract: A Cu metal‐organic framework (MOF), [Cu4(PMTD)2(H2O)3]⋅20 H2O, 1, (where PMTD is 1,4‐phenylenebis(5‐methyl‐4H‐1,2,4‐triazole‐3,4‐diyl)bis(5‐carboxylato‐3,1‐phenylene)bis(hydroperoxymethanide)), with a rare chiral Oh‐type cage, and dual functionalities of open metal sites and Lewis basic sites, based on a designed U‐shaped ligand, was synthesized by hydrothermal methods. It exhibits high CO2, C2, and C3 hydrocarbon storage capacity under atmospheric pressure, as well as high H2 (1.96 wt.%) adsorption capacity at 77 K. Methane purification capacity was tested and verified step by step. Isosteric heats (Qst) studies reveal that CH4 has the weakest van der Waals host–guest interactions among the seven gases at 298 K. Ideal adsorbed solution theory (IAST) calculation reveals that compound 1 is more selective toward CO2, C2H6, and C3H8 over CH4 in further calculating its separation capacity, as exemplified for CO2/CH4 (50:50, 5:95), C2H6/CH4 (50:50, 5:95), or C3H8/CH4 (50:50, 5:95) binary gas mixtures. Breakthrough experiments show that 1 has a significantly higher adsorption capacity for CO2, C2H6, and C3H8 than CH4. The selective adsorption properties of 1 make it a promising candidate for methane purification. [ABSTRACT FROM AUTHOR]

Monodisperse and water-soluble lanthanide (Ln3+)-doped Y(Gd)VO4 nanocrystals (NCs) have been successfully synthesized by a fast, facile, and environmentally friendly microwave-assisted route with poly(acrylic acid) as the surfactant. The Y(Gd)VO4:5 %Ln3+ (Ln = Eu, Dy, Sm) NCs have unique fluorescence properties and polydimethylsiloxane (PDMS)-based white solid nanocomposites containing YVO4:5 %Eu3+ NCs show red emission upon UV irradiation. GdVO4 NCs can act as CT and MRI contrast agents as a result of their magnetic and X-ray absorption properties. A layer of SiO2 was coated onto the surfaces of the nanoparticles and MTT assays were carried out to test the cytotoxicity of the YVO4@SiO2 and GdVO4 NCs. The results indicate that the Y(Gd)VO4 NCs have potential in multimodal optical/MRI/CT bio-imaging. [ABSTRACT FROM AUTHOR]

Magnesium silicate double-walled hollow nanofibers (MSHNFs) with a hierarchical nanostructure have been successfully fabricated by combining the electrospinning technique with a hydrothermal method. The as-prepared MSHNFs are composed of numerous ultrathin nanosheets with a thickness of approximately 10 nm and have a high specific surface area (632.2 m2 g−1) and large pore volume (0.92 cm3 g−1). The MSHNFs exhibit high adsorption capacity and excellent stability in a purification test with organic molecules and a solution of heavy-metal ions. Moreover, the MSHNFs can be easily separated from solution by gravitational sedimentation owing to their unique structure. [ABSTRACT FROM AUTHOR]

Highly crystalline and uniform TiO2:Eu3+ spindlelike nanorods have been successfully synthesized through a facile hydrothermal route with citric acid (H3Cit) and ethanediamine (en) as the assistant agents for the first time. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), and photoluminescence (PL) spectroscopy were utilized to characterize the samples. In the synthetic process, the dosages of ethanediamine and citric acid are important parameters that affect the morphology and size of the final products. A possible formation process of the samples has been proposed in detail. The existence of Eu3+ sites in the TiO2 nanorods was proved by site-selective spectroscopy. Furthermore, the TiO2:Eu3+ spindlelike nanorods exhibit bright red (Eu3+, 5D0→7F2) luminescence under ultraviolet (UV) excitation; therefore, they may find potential applications in fluorescent lamps and field-emission displays (FEDs). [ABSTRACT FROM AUTHOR]