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Abstract: Gold nanochains ranged from several hundred nanometers to more than 5μm were synthesized by a modified citrate reduction method. The synthesized nanochains have been characterized by TEM, AFM and UV absorption spectrum. The produced nanochains can be transferred onto the mica surface, and can bear the repeating scan by AFM tip, which may have some potential applications in electronics and catalysis. [Copyright &y& Elsevier]

Underwater superoleophobic surfaces are based on the surface with micro-/nanoscale roughness and hydration layer. But the self-cleaning surfaces are usually mechanically weak and will lose their underwater superoleophobicity when the surfaces are corroded or damaged. In this paper, to overcome these problems, the robust underwater superoleophobic coating (HN/ER-coating) has been fabricated successfully through MPS (methacryloxy propyl trimethoxyl silane)-SiO 2 /PNIPAM ( N -isopropylacryamide) hybrid nanoparticles and epoxy resin (ER) via a simple solution-casting method. The SiO 2 /PNIPAM hybrid nanoparticles can enhance multiscale roughness and excellent abrasion-resistant property, and the epoxy resin can be used as an interlayer between hybrid nanoparticles and substrates to promote the robustness and corrosion resistance of the coating. The obtained coatings have excellent underwater superoleophobicity, and exhibit highly stability in harsh environments (including acid-base, strong ionic strength, mechanical abrasion). Moreover, this coating can provide protective effect on the substrate in corrosive solution, and may also resist bacterial attachment and subsequent biofilm formation because of the presence of high density PNIPAM polymers. Herein, the developed underwater superoleophobic coating can be applied as an effective platform for the applications in underwater instruments, underwater oil transport, marine oil platform and ships. [ABSTRACT FROM AUTHOR]

[Display omitted] • A gel-based ZnO-Cu catalyst with high activity and recyclability is prepared. • The coagulating bath plays an important role in the network structure of CCG. • The network structure of CCG affects the morphologies of ZnO-Cu nanoparticles. • Flower-like structure improves the surface reactivity of the ZnO-Cu/CCG catalyst. • ZnO-Cu/CCG can be reused over 50 cycles without evident loss of catalytic efficiency. The recyclability of heterogeneous catalysts directly affects their utilization efficiency, use cost, sustainability, and environmental issues. Herein, the flower-like ZnO-Cu nanoparticles with high interfacial reactivity were in-situ synthesized in the porous cellulose gel to obtain the ZnO-Cu/cellulose composite gel (ZnO-Cu/CCG) catalyst, which possesses superior recycling and reusing stability thanks to the bulk nature of the gel. The ZnO-Cu/CCG catalysts with tunable sheet-like and flower-like ZnO were fabricated by the dissolution of cellulose into zinc chloride (ZnCl 2) solvent and regeneration using different coagulating baths (water, ethanol, or isopropanol). The CCG prepared from isopropanol coagulation exhibited the highest specific surface area (291.6 m2/g) and porosity (92.3%). The various network structures of CCG provided different nucleation sites and growing spaces for controllable preparation of ZnO with tunable morphology. The complete removal of methyl orange (MO), Congo red (CR), and methylene blue (MB) required only 80 sec, 3 min, and 5 min, using flower-like ZnO-Cu/CCG catalysts prepared by isopropanol coagulating bath, the pseudo-first-order rate constant (k) is 2.8170 min−1, 1.1330 min−1, and 0.8506 min−1, respectively, much higher than that of the ZnO-Cu powders. Furthermore, the catalytic reusability of ZnO-Cu/CCG can be investigated over 50 successive cycles, in which the catalytic efficiency did not decrease appreciably. [ABSTRACT FROM AUTHOR]

Abstract: Silver nanoparticles ring was successfully fabricated by electrostatic assembling 4-aminothiophenol (4-ATP) capped silver nanoparticles on predefined extended circular plasmid pBR322 DNA. The silver nanoparticles ring which was about 1.5μm in length, and about 2.2nm in height can be obtained by adjusting the reaction time. The normal Raman scattering spectra reveal that the 4-ATP has contacted with the silver nanoparticles by forming a strong Ag–S bond. The AFM data show that the assembly of 4-ATP capped silver nanoparticles on DNA is ordered. [Copyright &y& Elsevier]

Abstract: In this paper, a method for highly ordered assembly of cuprous oxide (Cu2O) nanoparticles (NPs) by DNA templates was reported. Cetyltrimethylammonium bromide (CTAB)-capped Cu2O NPs were adsorbed onto well-aligned λ-DNA chains to form necklace-like one-dimensional (1D) nanostructures. UV–vis, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) were used to characterize the nanostructure. The Cu2O nanostructures fabricated with the method are both highly ordered and quite straight. [Copyright &y& Elsevier]

Abstract: Cetyltrimethylammonium bromide (CTAB)-capped positively-charged silver nanoparticles synthesized in water–ethanol system was electrostatic assembled on predefined aligned λ-DNA template. Silver nanowire can be obtained by changing the reaction time and the particles concentration. In our work, the length of the silver nanowire obtained is about 10μm, and the dimension of the wires is about 20nm. AFM data reveal that the assembly of CTAB-capped silver nanoparticles on DNA is ordered, but there is space between two particles absorbed on the DNA template. X-ray photoelectron spectroscopy (XPS) was applied to characterize the linear silver clusters, which provides an additional proof that the silver particles were assembled onto DNA template with fine order. [Copyright &y& Elsevier]