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The maghemite particulate nanosheets (MPNs) are prepared in solvothermal system by connecting the nanoparticles in two-dimension. The interconnected MPNs sustain a mesopores structure with a high accessible surface area of 164 m2/g, and have a high performance for Cr6+ adsorption. The Cr6+ removal process fit with Langmuir adsorption model with an adsorption capacity of 20.41 mg/g. The purified solution could reach a residual concentration of 0.002 mg/L for MPNs, which is much less than the concentration in the solution of 0.249 mg/L when the nanoparticles are used. The synthesized MPNs with a saturation magnetization of 70.51 emu/g at room temperature can be easily collected and separated by an external magnet in liquid. Exchange coupling and shape anisotropy are the main reason for the higher Ms of MPNs. The unique structure with large surface area and high saturation magnetization make the MPNs favourable for the application of magnetic separation.

The design of efficient catalysts for the selective oxidation of sp3 C–H bond with air at low temperature is of great importance to the scientific and industrial community. In this work, we design a CeO2–δ modified CuFe2O4 catalyst by a post‐modification method for the selective oxidation of fluorene under an air atmosphere and N‐hydroxyphthalimide (NHPI) at 60 °C. HRTEM results indicate that CeO2–δ nanoclusters sized around 5 nm are successfully modified on the surface of CuFe2O4. XPS and H2‐TPR results show that CeO2–δ modification would favor oxygen transfer at lower temperature due to the synergetic effect between CuFe2O4 and CeO2–δ with rich Ce3+/Ce4+ couples. The results demonstrate that CuFe2O4@CeO2–δ‐0.05 with 4.20 wt.‐% Ce present the best catalytic performance with 94 % conversion of fluorene and excellent reusability at least five times. It is anticipated that the modification of CeO2–δ nanoclusters on the surface leads to increased oxygen activation and transfer to CuFe2O4, which favors the activation of NHPI to phthalimide‐N‐oxyl (PINO) radicals and exhibits an improved catalytic performance. Our results provide some guidance on the design of efficient catalysts by the surface modification strategy. CeO2–δ modification with 4.20 wt.‐% Ce on the surface of CuFe2O4 nanoparticles favors oxygen transfer at lower temperature and leads to better catalytic activity than that of pure CuFe2O4 for the aerobic selective oxidation of fluorene due to the synergetic effect between CuFe2O4 and CeO2–δ with Ce3+/Ce4+. [ABSTRACT FROM AUTHOR]

Air-stable metallic Co nanoparticles were incorporated into the pores or anchored onto the external surface of an ordered mesporous carbon/SBA-15 composite by simply treating the cobalt precursor-impregnated surfactant-containing SBA-15 via the Reaction under Autogenic Pressure at Elevated Temperature (abbreviated to RAPET) process, resulting in bifunctional Co@carbon/SBA-15 composites. Surfactant-containing mesoporous SBA-15 (denoted as surf-SBA-15 composite) was firstly impregnated with a cobalt precursor solution and then calcined under autogenic pressure at elevated temperature using a Swagelok-like high-temperature autoclave in an N2 atmosphere. During the RAPET process, the cobalt precursor impregnated into the channel of the surf-SBA-15 composites decomposed and was reduced by the surfactant species, meanwhile, the surfactant, which was used as a soft template for the formation of mesoporous silica, was carbonized and coated onto the internal and the external surface of mesoporous silica and partially onto the incorporated metallic Co nanoparticles, forming Co nanoparticles encapsulated by a mesoporous carbon/SBA-15 composite (mesoporous Co@carbon/SBA-15) in situ. The products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption–desorption measurements and X-ray diffraction (XRD). The influences of the concentration of cobalt precursors on the morphologies and the magnetic properties of the mesoporous Co@carbon/silica composites were studied. The adsorption/separation ability of the magnetic mesoporous composite to organic guest molecules and the stability of the nanosized metallic Co decorations in air or in an acid environment were also investigated. [ABSTRACT FROM AUTHOR]

BiVO nanoparticles are prepared by molten salt method. Tetragonal BiVO completely transforms to monoclinic phase after heating in molten LiNO at 270 °C for 18 h. The average particle sizes of monoclinic BiVO varied from 30 to 52 nm while the initial ratio of BiVO to LiNO changes from 1:6 to 1:24. The photocatalytic activity is evaluated by measuring decolorization of N, N, N′, N′-tetraethylated rhodamine dye solution under visible-light irradiation. Both of the de-ethylation and chromophore cleavage are responsible for the decolorization of RB. The sample with an average particle size of 52 nm and a moderate surface area of 10 m/g exhibit the highest visible-light photocatalytic activity. The shift of Raman peak position indicates that the symmetry distortions in the local structure of the monoclinic BiVO. The variations of the local structure result in the modification of the electronic structure, which is responsible for the high visible-light photocatalytic activity. [ABSTRACT FROM AUTHOR]

The self-assemble propensity of the controlled shape and size distribution titania nanoparticles makes the particles oriented organization to ordered structures without substrate by a hydrolysis-hydrothermal route. The procedure offers the possibility of a generalized approach to the production of patterned organization of single and complex oxide nanoparticles with size and morphology tunable. [Copyright &y& Elsevier]

La1−xSrxMnO3 (x=0.3) (LSM) nanoparticles were prepared by a sonication-assisted coprecipitation method. The coprecipitation reaction is carried out with ultrasound radiation. Lower sintering temperatures are required for the sonication-assisted product. Fully crystallized LSM with an average particle size 24 nm is obtained after the as-prepared mixture is annealed at 900 °C for 2 h. Magnetic properties indicate that the transition temperature from the paramagnetic to ferromagnetic state of the sample is quite sharp and occurs at 366 K for samples annealed for 2 h at 900 and 1100 °C. [Copyright &y& Elsevier]

Nanoparticles of Al-doped SnO2 have been hydrothermally synthesized. The influences of the hydrothermal reaction time, the molar ratio of Sn/Al as well as the pH value of the solution have been studied. During the hydrothermal synthesis, the particle’s core is rich in Sn and the surface is rich in Al. The Al-rich surface prevents the particles from further growing up either in the hydrothermal condition or during the calcination at 600 °C for a short period of time. The optimal hydrothermal synthesis condition of the nanoparticles is pH 5, Sn/Al=4:1 and 12 h at 160 °C. The products have been studied by XRD, TEM and 27Al solid-state NMR. [Copyright &y& Elsevier]

[Display omitted] • An underliquid dual superlyophobic membrane with hierarchical micro/nanostructure is constructed. • The underliquid dual lyophobicity of polyethersulfone nanoparticles and the microporous structure formed by Zn-Ni-Co LDH nanowires synergistically contribute to the underliquid dual superlyophobic performance. • The underliquid dual superlyophobic membrane is beneficial for the separation of organic liquid/water emulsions. • The proposed strategy is effective for preparing underliquid dual superlyophobic membranes with various supporters. A hierarchical micro/nanostructure has been successfully fabricated, which is constructed by anchoring polyethersulfone (PES) nanoparticles on Zn-Ni-Co layered double hydroxide (LDH) nanowires with stainless steel mesh as supporter (PES/PDA@ZNCNW-SSM). The PES/PDA@ZNCNW-SSM shows excellent underliquid dual superlyophobicity with underwater tetrachloroethylene contact angle and under n-hexane water contact angle of 166.7° and 166.8°, respectively. The underliquid dual lyophobic PES and microporous structure formed by Zn-Ni-Co LDH nanowires synergistically contribute to the underliquid dual superlyophobic surface, which is beneficial for effective and controllable organic liquid/water separation. After 10 cycles of alternate separation, the separation efficiencies of PES/PDA@ZNCNW-SSM are above 99.9% and 99.4% for water-in-tetrachloroethylene and tetrachloroethylene-in-water emulsions, respectively. The underliquid dual superlyophobicity can also be obtained with carbon cloth, non-woven fabric, Ni foam and filter paper as supporter and the corresponding membranes can be used to efficiently separate organic liquid/water mixtures on-demand. These results confirm that the hierarchical micro/nanostructure anchored with underliquid dual lyophobic PES nanoparticles is an effective route for the preparation of underliquid dual superlyophobic materials. [ABSTRACT FROM AUTHOR]

• The TSTN ultrafiltration membrane is fabricated via facilely depositing and sintering. • The TSTN ultrafiltration membrane has both high permeability and high rejection. • BSA can be efficiently rejected by TSTN ultrafiltration membrane. • The separation mechanism to BSA is discussed in detail. • The TSTN ultrafiltration membrane has excellent anti-fouling and regeneration property. Both high permeability and high selectivity are advantageous for separation membrane materials. It is a huge challenge to fabricate a membrane that simultaneously possesses both high permeability and high rejection. Here, we fabricated a TiO 2 nanofibers ultrafiltration membrane by depositing hydrogen titanate nanofibers on a porous titanium substrate and sintering at 450 °C. The porous titanium supported TiO 2 nanofibers ultrafiltration membrane has a superhydrophilic separation layer and a high pure water flux of 940 L m−2 h−1 bar−1. The average pore size of the TiO 2 nanofibers ultrafiltration membrane is 14 nm. The nanoparticles that particle size is smaller than pore size of TiO 2 nanofibers ultrafiltration membrane such as Bovine serum albumin (BSA, 11 nm) and 3 nm TiO 2 nanoparticles can be rejected with high permeation flux and high rejection efficiency. The obtained ultrafiltration membrane exhibits excellent antifouling property, the flux recovery ratio reaches to 97%. Also, the fouling of the TiO 2 nanofibers ultrafiltration membrane can be removed by heating treatment, the permeation flux of the membrane can be easily recovered. [ABSTRACT FROM AUTHOR]