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Abstract Owing to the diverse structures and unique characteristics of MOFs, the combination of magnetic particles with porous MOFs is an attractive way for rapid and efficient extraction of organic pollutions from water. In this work, the magnetic porous composites, Fe 3 O 4 -PSS@ZIF-67 (PSS, poly (sodium-p-styrenesulfonate)), were prepared. The obtained composites exhibit core-shell structure, for which the spherical Fe 3 O 4 particles as core are embedded in ZIF-67 shell. The existence of SO 3 − anions on poly (sodium-p-styrenesulfonate) is the key factor for the uniform coating of ZIF-67 on Fe 3 O 4 particles. Poly (sodium-p-styrenesulfonate) providing enough chelating sites (-SO 3 −) for Co2+ which could further coordinate with 2-methylimidazole to form ZIF-67. This work further studied the adsorption property of 2-nitroresorcinol in aqueous solution, using Fe 3 O 4 -PSS@ZIF-67 as adsorbents. The equilibrium adsorption capacity for 2-nitroresorcinol is up to 52.50 mg g−1. The adsorption kinetics were investigated. The mechanism could be attributed to the electrostatic interaction between 2-nitroresorcinol and Fe 3 O 4 -PSS@ZIF-67 composites. Graphical abstract A new magnetic porous composites (Fe 3 O 4 -PSS@ZIF-67) was prepared, for which poly (sodium-p-styrenesulfonate) links the spherical Fe 3 O 4 core and ZIF-67 coating. The composites perform well on nitrophenol from aqueous solution via magnetic separation operation, mainly owing to the porosity of ZIF-67 and the electrostatic interaction between nitrophenol and composites. The combination of magnetic separation with MOFs is attractive way for efficient removal of nitrophenols from waste water. fx1 [ABSTRACT FROM AUTHOR]

A novel photochromic nanocomposite film containing polyoxotungstoeuropate K12[EuP5W30O110] entrapped in polyvinylpyrrolidone has been prepared through a spin-on coating technique. Thus-obtained amorphous nanocomposite film was characterized by IR spectra, UV–vis absorption spectra, XRD, SEM, TG-DTA, and ESR. Results show that polyoxotungstoeuropate interacts with polyvinylpyrrolidone strongly and disperses homogeneously in the matrix. The composite film exhibits good photochromic properties. When irradiated with UV light, the transparent film changes from colorless to blue. Then, bleaching occurs when the film is in contact with ambient air or O2 in the dark. The photochromism of the composite film is due to charge transfer by reduction of polyoxotungstoeuropate and oxidation of polyvinylpyrrolidone. [Copyright &y& Elsevier]

1-D nanorods, twinrods, golfclubs, and tripods of CdS were prepared via a surfactant–ligand co-assisted solvothermal method at 160°C. The surfactant of S-dodecylisothiounium bromide (C12) used in the process was favorable for synthesis of different-shaped CdS nanorod with high aspect ratio. X-ray diffraction (XRD) and TEM images showed that the 1-D nanorods had wurtzite phase and others had a zinc blende core and wurtzite arms. The morphologies of CdS prepared under different conditions suggested the “template-assistance” of the surfactant and that the nonaqueous organic media are important for the self-assembling of inorganic components at atomic level. [Copyright &y& Elsevier]

A novel thermochromic sol–gel film has been prepared for the first time through entrapping phosphomolybdic acid into a kind of inorganic–organic matrix co-hydrolyzed from tetraethylorthosilicate and 3-aminopropyltriethoxysilane. The thus-obtained amorphous nanocomposite film was characterized by IR spectra, UV–vis absorption spectra, XRD, TG–DTA, and ESR. Results show that phosphomolybdate polyanions interact with R–NH+3 cations strongly and disperse homogeneously in the sol-gel matrix. The sol–gel film exhibits thermochromic properties. Annealed from 120 to 180°C, the transparent film changes from pale-yellow to blue. A possible charge-transfer process has been suggested to explain the thermochromism. [Copyright &y& Elsevier]

Novel photochromic nanocomposite thin film containing phosphotungstic acid entrapped in polyacrylamide was prepared using ultrasound technique. TEM image revealed that the polyoxometalates nanoparticles with narrow size distribution were finely dispersed in polymer matrix. IR spectra showed that the Keggin geometry of polyoxometalates was still preserved inside the composite film and strong Coulombic interaction was built between heteropolyoxometalates and polyacrylamide via hydrogen bond. It was found that the thermal stability of the hybrid film was lower than that of pure polymer but the film was stable enough for photochromic application from the TG–DTA curves. The transparent film changed from colorless to blue under UV irradiation and showed reversible photochromism. The bleaching process occurred when the film was in contact with air or O2 in the dark. The photoreduced process was in accordance with radical mechanism. [Copyright &y& Elsevier]