Nanosphere, hollow

Even though Ti02-based materials have been far more investigated than any other photocatalyst and this chapter is dedicated to these systems, it is important at least to mention here some of the promising alternative materials studied for wastewater treatment. CdS hollow nanospheres were prepared in a single-step hydrothermal route by Li et al. [109] using the ionic liquid l-butyl-3-methylimidazolium... 

Li, X., Gao, Y., Yu, L., and Zheng, L. (2010) Template-free synthesis of CdS hollow nanospheres based on an ionic liquid assisted hydrothermal process and their application in photocatalysis. Journal of Solid State Chemistry, 183 (6), 1423-1432. 

Preparation of Cu20 hollow nanospheres under reflux conditions. European Journal of Inorganic Chemistry, 3841-3844. 

Cao, C., Cui, Z., Chen, C., Song, W. and Cai, W. (2010) Ceria hollow nanospheres produced by a template-free microwave-assisted hydrothermal method for heavymetal ion removal and catalysis. Journal of Physical Chemistry C, 114, 9865-9870. 

Fig. 4.2 TEM images of fabricated nanoparticles, (a) Isolated composite core/shell submicron particles, (b) Hollow silica submicron particles prepared by removing the polystyrene core to demonstrate the high quality of the formed sol gel shell of the composite nanospheres employed to prepare sensing colloidal crystal films...

Figure 6.4 The preparation of nanostructured materials in solution evolves from (a) the classic examples of suspension, dispersion, or emulsion polymerization, to the methods that include the covalent crosslinking of select domains within supramolecular polymer assemblies (b) core crosslinking of polymer micelles (c) shell crosslinking of polymer micelles (SCKs) (d) nanocages from core-eroded SCKs (e) shaved hollow nanospheres from outer shell/core-eroded vesicles.

Figure 6.5 Illustrations of nanoscale spherical assemblies resulting from block copolymer phase separation in solution are shown, along with the chemical compositions that have been employed to generate each of the nanostructures (a) core crosslinked polymer micelles (b) shell crosslinked polymer micelles (SCKs) with glassy cores (c) SCKs with fluid cores (d) SCKs with crystalline cores (e) nanocages, produced from removal of the core of SCKs (f) SCKs with the crosslinked shell shielded from solution by an additional layer of surface-attached linear polymer chains (g) crosslinked vesicles (h) shaved hollow nanospheres produced from cleavage of the internally and externally attached linear polymer chains from the structure of (g)...

The advances in nanotechnology and synthesis methods have enabled nanomaterials to be produced in various shapes and structures. Coating of a luminescent layer activated by lanthanide ions on nanoparticles such as SiC>2 or AI2O3 is one of such approaches to develop new nanophosphors. In section 6, we review recent work on interesting spectroscopic features and luminescence dynamics of lanthanide ions in other novel low-dimensional nanostructures including core-shell, one-dimensional (ID) nanowires and nanotubes, two-dimensional (2D) nanofilms, hollow nanospheres, 2D nanosheet and nanodisk which have also attracted extensive attention. 

It is possible to alter the intrinsic properties of materials by chemical nanocoating, which cannot be achieved by conventional methods. Generally the core-shell nanostructures are divided into two categories (1) lanthanides doped in the core (2) lanthanides doped in the shell. The former are synthesized in order to improve the quantum efficiency of lanthanide ions or design bio-labels, while the latter are meant for the study of surface modifications on the lanthanide luminescence or the synthesis of lanthanide-doped hollow nanospheres. 

Liu et al. synthesized hollow nanospheres of Eu Y2C>3 (20 nm shell thickness) by etching SiC /Y2O3 Eu core-shell nanoparticles with NaOH solution (Liu and Hong, 2005). No significant difference in emission spectrum was observed for both the hollow nanospheres and their core-shell counterparts. 

To what extent can the example of a solid exoskeleton be replicated in the laboratory Going against most contemporary examples of flexible artificial cells, Muller and Rehder published an example of a complex molybdenum oxide that spontaneously forms discrete nanospheres [23], The hollow spheres were porous and allowed lithium cations to pass through the exoskeleton. While this a perhaps an extreme example of what may be considered an artificial cell, the authors assert that the presence of ion selective channels through the encapsulating oxide is directly analogous to natural ion channels in organic cells. 

In general, microgels obtained by radiation methods can be used in various applications in the same way as conventional synthesized systems, e.g., as drug delivery templates, for encapsulation, or as microreactors [29, 30], PAAm for example can be used as template material to synthesize hollow cadmium selenide nanospheres [24], and PVP can be used for the incorporation of ferromagnetic nanoparticles to obtain magnetic hydrogel microspheres [13],... 

Hu Y, Chen JF, Chen WM, Ning JQ (2004) Preparation of hollow CdSe nanospheres. Mater Lett 58(22—23) 2911—2913... 

Zhou P, Li Y, Sun P, Zhou J, Bao J (2007) A novel Heck reaction catalyzed by Co hollow nanospheres in ligand-free condition. Chem Commun 1418-1420... 

By using polymer-controlled growth in ethylenediamine at 170°C, very long CdS nanowires (100px40 nm) were synthesized (Fig. 9a) [36]. Cadmium sulfide with different morphologies, such as nanoparticles and nanorods (Fig. 9b) [39], peanut-like nanostructures [37] and hollow nanospheres [38] (Fig. 9c) were prepared via solvothermal routes. 

In order to improve the kinetics of the Li-N-H system, Xie et al. [96] prepared Li2NH hollow nanospheres by plasma metal reaction based on the Kirkendall effect. The special nanostructure showed significantly improved hydrogen storage kinetics compared to that of the Li2NH micrometer particles. The absorption temperature decreased markedly, and the absorption rate was enhanced dramatically because... 

Chon H, Lee S, Son SW, Oh CH, Choo J (2009) Highly sensitive immunoassay of lung cancer marker carcinoembryonic antigen using surface-enhanced Raman scattering of hollow gold nanospheres. Anal Chem 81 3029... 

Nanospheres are hollow nanosized particles (Figure 47.1C) that can be prepared by microemulsion polymerization or covering the surfaces of colloidal templates with thin layers of the desired material followed by selective removal of the templates (Hyuk Im et al., 2005). The carboxylated polystyrene nanospheres (20 nm) were evaluated for drug delivery... 

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