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A visible light-driven AgBr/Ag 2 CO 3 nanosheets composite has been fabricated via a in-situ ultrasonic anion-exchange method at room temperature, using Na 2 CO 3 and cetyltrimethyl ammonium bromide (CTAB) as carbonate anion and bromide anion resources, respectively. The X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) analysis demonstrated that the obtained products were consisted of AgBr nanoparticles and Ag 2 CO 3 nanosheets, in addition the AgBr nanoparticles were well distributed on the surface of sheet-like Ag 2 CO 3 to form AgBr/Ag 2 CO 3 heterostructure. Evaluation of the prepared AgBr/Ag 2 CO 3 hybrids photocatalytic activity by degradation of Rhodamine B (RhB) or Methyl orange (MO) under visible light irradiation (λ>420 nm) indicated they have efficient and higher photocatalytic activities compared to the pure AgBr and Ag 2 CO 3 samples, which could be related to the matched band potential band potential between AgBr and Ag 2 CO 3 . Besides, a possible photocatalytic mechanism of the hybrids was also proposed.

In this letter, graphene oxide (GO) was prepared by a kind of modified Hummers' method, which via ultrasonic treatment could be dispersed in water to obtain a homogeneous and stable brownish yellow flocculent solution. AgBr/Ag/Ag2O/GO nanocomposite catalyst was produced by adding hexadecyltrimethyl ammonium bromide (CTAB) and silver nitrate solution into the above formed GO solution under ultrasonic treatment. The structures, morphologies, and light absorption properties of AgBr/Ag/Ag2O/GO composite catalysts were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and ultraviolet and visible diffuse reflectance spectroscopy (UV-DRS). Preliminary results showed that the composite catalyst has a better catalytic degradation effect on organic dyes like rhodamine B (RhB) and methyl orange (MO) in polluted water under simulated solar light irradiation in contrast to the single GO and AgBr.

Hierarchically structured hollow microspheres composed of copper sulfide (CuS) nanoplatelets have been successfully fabricated via a one-pot and green sonochemical process for the first time, using copper acetate and thiourea aqueous solution as precursors without surfactant or template. Large-scaled hollow architectures with outer diameters in the range of 1–1.2 μm are assembled by pure hexagonal single crystalline CuS nanoplatelets, being of about 20 nm in thickness with stacking faults in the crystal lattice. The UV-Vis diffuse reflectance spectra (DRS) analysis suggests that the band gap energy of the as-obtained CuS sample was estimated to be 1.27 eV, showing a significant red-shift compared with the bulk value. Hollow CuS structures possess the high surface area and double pore size distributions as measured from the N2 adsorption isotherms. Moreover, the possible growth mechanism for CuS hollow spheres is proposed on the basis of the temporal evolution controlled experiments. More importantly, this hierarchically structured CuS catalyst show highly efficient Fenton-like catalytic activity in degrading highly concentrated dye-containing solution (50 mg·mL−1) with the help of hydrogen peroxide (H2O2), suggesting a promising application in wastewater purification.

Flammability performance and the microstructure of chars from poly(vinyl alcohol) (PVA) with α-type zirconium phosphate (α-ZrP) and montmorillonite (MMT) hybrid composites and multilayer composite were elucidated with microscale combustion calorimetry (MCC) and scanning electron microscopy (SEM). MCC revealed that the combination of α-ZrP and MMT did not impart synergistic effect in improving flame retardancy to PVA/ZrP/MMT hybrid composites, while multilayer composite showed better flame-resistant properties than hybrid composite. SEM demonstrated that the minimal loading levels of MMT in PVA/ZrP/MMT composites obstructed the development of intumescent chars in hybrid composites, but on-site mechanically reinforced the intumescent char in multilayer composite.

The mechanical properties and flame retardancy of linear low-density polyethylene/ethylene-propylene-diene terpolymer thermoplastic elastomers (TPEs) containing magnesium hydroxide sulfate hydrate (MHSH) whiskers and their corresponding un-vulcanized blends (UVBs) were evaluated using static tensile measurements, cone calorimetry and limiting oxygen index (LOI) tests. TPEs exhibited better fire-resistant properties in reducing peak heat release rate and improving LOI values to UVBs. Scanning electron microscopy (SEM) images showed that TPE sample left a more compact char after cone test. Results from tensile tests confirmed that TPEs had superior mechanical properties to UVBs due to the better compatibility between MHSH whiskers and polymer matrix.

A novel indexable TiC-based cermet tool (named tool A) with intra/intergranular microstructure has been designed and fabricated in application of face milling of a medium carbon steel (AISI 1045) in the dry condition comparison with commercial WC-Co tool (named tool B). Compared to the tool B, the newly as-prepared cermet tool A had an advantage of high speed cutting performances in cutting carton steel. Wear behavior was investigated in order to better understand the relationship between outstanding cutting properties and microstructure. The improved cutting performance of tool A can be attributed to the rim reinforced by TiN nanoparticles.

This paper presents the results of a study in which nanosized titanium dioxide (TiO{sub 2}) crystal particles were coated onto the surface of palygorskite fibrous clay which had been modified by silver ions using titanium tetrachloride as a precursor. Coated TiO{sub 2} particles with the anatase structure were formed after calcining at 400 deg. C for 2 h in air. Various analytical techniques were used to characterize the surface properties of titanium dioxide particles on the palygorskite. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses showed that TiO{sub 2} particles were supported on the surface of the palygorskite clays and their size was in the range of 3-6 nm. The titanium oxide coatings were found to be very active for the photocatalytic decomposition of methylene blue.

Mingguang palygorskite clays, when modified with the silver and copper ion may be useful in removing bacteria from aqueous solution. The antibacterial effect of these modified clays were investigated using Escherichia coli and Staphylococcus aureus as indicators of fecal contamination of water. Introduction of Ag+ or Cu2+ did not change the crystal structure of the Mingguang palygorskite. It was found that the Mingguang silver and copper palygorskite minerals eliminated the pathogenic microorganisms E. coli and S. aureus from water with the average amount of silver and copper supported on the minerals after 12 h of contact time.

Porous magnetite (Fe 3 O 4 ) microspheres can be direct acquired by hydrothermal reaction of Fe-citrate complex (Fe (NH 4 ) 2 H (C 6 H 5 O 7 ) 2 ) in neutral solution. Results show that the obtained Fe 3 O 4 particles are nearly spherical in shape and about 2 μm to 3 μm in mean diameter. Every magnetite microsphere is made of many ultrafine Fe 3 O 4 nanoparticles and porous in structure. The as-prepared porous magnetite microspheres have higher surface area (~ 83 m 2 /g) and excellent magnetic properties (M s = 81 emu/g, H c = 145 Oe) at room temperature.

Step-wise self-assembled flower-like δ-Bi2O3 microspheres from nanoparticles to nanosheets to microspheres were fabricated via a simple hydrothermal process, using glycine and Bi (NO3)3·5H2O as starting materials without other additives. The crystal structures and morphologies of the as-obtained samples were characterised by X-ray powder diffraction, field emission scanning electron microscope and transmission electron microscopy. The UV–vis diffuse reflectance spectrum of the sample showed the product has an intense absorption in UV light regions and an estimated bandgap 3.55 eV. Moreover, under UV-light irradiation the sample exhibited high photocatalytic behaviour for the degradation of rhodamine B dye and excellent stability, which possibly has a board application in wastewater disposal fields.