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ABSTRACT: Hierarchical In(2)O(3) rod-like microbundles were fabricated via the Pluronic F127-(EO(106)PO(70)EO(106)-) assisted hydrothermal reaction followed by calcining the In(OH)(3) precursors. The results revealed that the In(2)O(3) microarchitectures were constructed with well-aligned one-dimensional (1D) single-crystalline nanorods with highly uniform morphologies and particular exposed facets. Structural analysis suggested that the In(2)O(3) nanorods were enclosed by {110} and {001} facets. The triblock copolymer acted as a structure-directing agent and played a key role in the formation of In(OH)(3) microbundles. The formation of the precursors In(OH)(3) microbundles was studied through contrastive experiments and computational simulation, which can be contributed to the soft-template-directed self-assembly mechanism. The gas sensing properties of the as-prepared In(2)O(3) microbundles were investigated. Compared to the samples prepared in the absence of F127, the In(2)O(3) microbundles exhibited a superior sensing performance toward 2-chloroethanol vapor, which can be explained by hierarchically ordered structures and exposed crystal surfaces.
Journal of Colloid and Interface Science 02/2011; 354(1):89-93. · 3.07 Impact Factor
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Berichte der deutschen chemischen Gesellschaft 06/2010; 2010(21):3348 - 3353. · 2.94 Impact Factor
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ABSTRACT: One-dimensional (1D) heterostructures of uniform CdS nanowires separately decorated with hematite (α-Fe2O3) nanoparticles or magnetite (Fe3O4) microspheres were successfully synthesized via a two-step solvothermal deposition method. Each CdS nanowire had a uniform diameter of 40−50 nm and a length ranging from several to several tens of micrometers. Quasicubic α-Fe2O3 nanoparticles, with edge lengths up to about 30 nm, and Fe3O4 microspheres, with diameters of about 200 nm, anchored on nanowires free from any surface pretreatment form 1D dimer-type CdS/α-Fe2O3 semiconductor heterostructures or CdS/Fe3O4 semiconductor magnetic functionally assembled heterostructures. It was also found that α-Fe2O3 nanoparticles with a smooth surface were well-crystallized, and Fe3O4 microspheres with a relatively rough surface showed a polycrystalline nature. The relationship between the crystal structures and effects of lattice mismatch on the formation of heterojunctions were systematically investigated. The magnetic and optical properties and photocatalytic activities of the as-obtained heterostructures were separately investigated. The 1D CdS/Fe3O4 nanostructures displayed ferromagnetic properties of the Fe3O4 microspheres, and the photoluminescence behaviors of CdS nanowires were conserved in both heterostructures. The enhanced photocatalytic activity under visible light (λ > 420 nm) was observed in 1D CdS/α-Fe2O3 heterostructures due to fast charge separation.
08/2009;
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ABSTRACT: Metastable corundum-type In(2)O(3) hierarchical structures with various morphologies inherited InOOH nanostructures, which were generated via a catanionic-surfactant-assisted solvothermal process. The products were characterized in detail by x-ray powder diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and HRTEM. These superstructures were built from one-dimensional components. The one-dimensional preferential growth is explained in terms of the crystallographic features of InOOH. The effects of reaction parameters on the formation of nanostructures are also discussed. It is demonstrated that both laurylamine and oleic acid play an important role in the generation of InOOH hierarchical structures. Gas sensors composed of In(2)O(3) hierarchical nanostructures show a good response to toxic chlorophenol at 280 degrees C.
Nanotechnology 08/2009; 20(28):285501. · 3.98 Impact Factor
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Berichte der deutschen chemischen Gesellschaft 01/2009; 2009(7):897 - 902. · 2.94 Impact Factor
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ABSTRACT: The starch-stabilized Ag nanoparticles were successfully synthesized via a reduction approach and characterized with SPR UV/Vis spectroscopy, TEM, and HRTEM. By utilizing the redox reaction between Ag nanoparticles and Hg(2+), and the resulted decrease in UV/Vis signal, we develop a colorimetric method for detection of Hg(2+) ion. A linear relationship stands between the absorbance intensity of the Ag nanoparticles and the concentration of Hg(2+) ion over the range from 10 ppb to 1 ppm at the absorption of 390 nm. The detection limit for Hg(2+) ions in homogeneous aqueous solutions is estimated to be ~5 ppb. This system shows excellent selectivity for Hg(2+) over other metal ions including Na(+), K(+), Ba(2+), Mg(2+), Ca(2+), Fe(3+), and Cd(2+). The results shown herein have potential implications in the development of new colorimetric sensors for easy and selective detection and monitoring of mercuric ions in aqueous solutions. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11671-009-9387-6) contains supplementary material, which is available to authorized users.
Nanoscale Research Letters 01/2009; 4(10):1230-1235. · 2.73 Impact Factor
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ABSTRACT: One-dimensional (1D) CdS@ZnS core-shell nanocomposites were successfully synthesized via a two-step solvothermal method. Preformed CdS nanowires with a diameter of ca. 45 nm and a length up to several tens of micrometers were coated with a layer of ZnS shell by the reaction of zinc acetate and thiourea at 180 °C for 10 h. It was found that uniform ZnS shell was composed of ZnS nanoparticles with a diameter of ca. 4 nm, which anchored on the nanowires without any surface pretreatment. The 1D CdS@ZnS core-shell nanocomposites were confirmed by XRD, SEM, TEM, HR-TEM, ED, and EDS techniques. The optical properties and photocatalytic activities of the 1D CdS@ZnS core-shell nanocomposites towards methylene blue (MB) and 4-chlorophenol (4CP) under visible light (λ > 420 nm) were separately investigated. The results show that the ZnS shell can effectively passivate the surface electronic states of the CdS cores, which accounts for the enhanced photocatalytic activities of the 1D CdS@ZnS core-shell nanocomposites compared to that of the uncoated CdS nanowires.
Nanoscale Research Letters 01/2009; 4(6):558-64. · 2.73 Impact Factor
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ABSTRACT: A series of five carefully designed tris(phthalocyaninato) gadolinium triple-decker complexes [Pc(R)8]Gd[Pc(R')8]Gd[Pc(R'')8] (R=R'=R''=H; R=R'=H, R''=OC8H17; R=R''=H, R'=OC8H17; R=H, R'=R''=OC8H17; R=R'=R''=OC8H17) (1-5) were prepared and the film forming properties on water surface were systematically investigated. The limited mean molecular area obtained by pi-A isotherms revealed an "edge-on" conformation for all these compounds. UV-vis absorption spectra showed red-shifted Q bands, indicating the formation of J aggregates and effective intermolecular interaction in solid film. Phthalocyanine rings were found to take tilted orientation with respect to the normal of substrate according to the polarized absorption spectroscopic measurements. Low angle X-ray diffraction results provide direct evidence and therefore clearly clarify the point, for the first time, that unsymmetrical triple-decker molecules pack on the water surface with the unsubstituted phthalocyanine ring set close to the water surface and the substituted phthalocyanine ligand with octyloxy groups lies on the top.
Journal of Colloid and Interface Science 12/2006; 303(1):256-63. · 3.07 Impact Factor
