Nanocomposites core-shell

Preparation of Mg(OH)2/PMMA core-shell nanocomposite by emulsion polymerization... 

The reaction scheme for core-shell nanocomposite is illustrated in Fig. 1. The grafting of y-... 

Core-shell nanocomposite of Mg(OH)2/PMMA with an average particle size of ca. 500nm where Mg(OH)2 is the core and PMMA is the shell was successfidly prepared by the emulsion polymerization of MMA in the presence of surface modified Mj OH)2. The grapelike ( re-shell microspheres with PMMA nodules could he obtained as stable latex. 

Fig. 4. TEM micrograph of core-shell nanocomposite of y-MPS modified Mg(OH)2 withPMMA.

Hu, H., Xiong, L.Q., Zhou, J., etal. (2009) Multimodal-luminescence core-shell nanocomposites for targeted imaging of tumor cells. Chemistry —A European Journal, 15, 3577—3584. 

Chen, T.Y. and Somasundaran, R, Preparation of novel core-shell nanocomposite particles by controlled polymer bridging, J. Am. Ceram. Soc., 81, 140, 1998. 

Wang, D., He, J., Rosenzweig, N. and Rosenzweig, Z. (2004) Superparamagnetic Fe203 beads-CdSe/ZnS quantum dots core-shell nanocomposite particles for cell separation. Nano Lett., 4, 409—413. 

Li, Z. Gao, B. Chen, G. Z. Mokaya, R. Sotiropoulos, S. Li Puma, G. Carbon Nanotube/Titanium Dioxide (CNT/Ti02) Core-shell Nanocomposites with Tailored Shell Thickness, CNT Content and Photocatalytic/photoelectrocatalytic Properties. Appl. Catal., B, 2011, 110, 50-57. 

Yin, Z., Ding, Y, Zheng, Q., and Guan, L. (2012). CuO/potypyrrole core-shell nanocomposites as anode materials far lithium-ion batteries, Electrochem. Commun, 20, pp. 40-43. 

Figure 6.2 (Up) Schematic illustration of the synthesis procedure of SWNT/PANI core/ shell nanocomposites. (Down) Transmission electron microscopy (TEM) images of PANI/ SWNT nanocable composites. Adapted with permission from Ref. [5-6], Copyright 2010 American Chemical Society.

Kun et al. studied the TE properties of porous MWNT/PANI core/ shell nanocomposites [8]. The increased volume of nanopores makes a significant contribution to phonon scattering and the thermal annealing process improves the Seebeck coefficient of the as-produced nanocomposites. These two operations resulted in significant enhancement in... 

Core-shelled nanocomposite particles with polystyrene sphere core and ... 

PVK branches. As a result, ultrathin and robust a PVK shell was coated onto the surface of a PPy nanoseed. The shell thickness was controlled within the range of a few nanometers. Compared with pure PVK (conductivity, ca. 10 °Scm ), the core-shell nanoparticle showed superior conductivity (ca. 10 Scm ) and similar fluorescence, and revealed only 2-3% decrease in conductivity after 20 days because the shell protected the PPy core from environmental perturbation. Accordingly, this methodology opens up a route to the fabrication of similar core-shell nanocomposites through a broad selection of solvents, oxidizing agents, monomer types, and polymerization temperatures. 

Kim, H., Achermann, M., Balet, L.P., Holhngsworth, J.A., Khmov, V.L Synthesis and characterization of Co/CdSe core/shell nanocomposites bifimctional magnetic-opticrd nanocrystals. J. Am. Chem. Soc. 127, 544-546 (2005)... 

Another effective method is to achieve core-shell structured nanocomposites. The shells can be C and SiO. In the case of Carbon-coated nano-Si composite, the preparation is as follows as anode material for LIBs. At first, PAN-coated Si nanoparticles are formed by emulsion polymerization and the PAN-coated precursor is heat-treated under Ar to generate a Si-C core-shell nanocomposite (Fig. 5.4a). The conductive carbon shell envelops the Si nanoparticles and suppresses the aggregation of the Si nanoparticles during electrochemical cycling, subsequently ameliorating the capacity retention of this composite anode material (Fig. 5.4b). 

The Si-SiO core-shell nanocomposite is prepared by a sol-gel method in combination with a subsequent heat-treatment process. At first, molten Si with high purity was irradiated by laser and gasified under an Ar atmosphere, and the condensed Si nanoparticles were collected on a water-cooled wall. Then, the obtained Si nanoparticles were dipped into a stirred tetraethylorthosilane (TEOS) sol, followed by the processes of pH adjustment, aging, drying, and heat treatment. Finally, a core-shell structured Si-SiO nanocomposite was synthesized. Because the Si-hydroxyl groups in the TEOS sol possess high activity, the silica gel can be easily adsorbed onto the surface of the Si nanoparticles. The as-synthesized Si-SiO composites yield a core-shell structure. Besides, the crystalline structure of the obtained SiO shell is highly... 

Figure 5.15 Discharge and charge profiles of (a] the anatase nano-Ti02 particles and (b) rutile Ti02-carbon core-shell nanocomposite at a constant current density of 0.1 mA/cm in the voltage range 1.4-2.5 V. Reprinted from Ref. 71, Copyright 2006, with permission from Elsevier.

Yang, J., Deng, L.-H., Han, C.-R., Duan, J.-F., Ma, M.-G., Zhang, X.-M., Xu, F., Sun, R.-C., 2013a. Synthetic and viscoelastic behaviors of silica nanoparticle reinforced poly(acrylamide) core-shell nanocomposite hydrogels. Soft Matter 9, 1220—1230. 

Peng, Y.-K. et al, (2011) A new and facile method to prepare uniform hollow MnO/fimctionalized mSi02 core/shell nanocomposites. ACS Nano, 5 (5), 4177-4187. 

Figure 46.4 Schematic diagram of the formation procedure of Ag nanoparticle-modified sol-gel sMica graphene oxide core/shell nanocomposites. (Adapted with permission from Ref [26].)...

S. Mao, W. Li, Y. Long, Y. Tu, A. Deng, Sensitive electrochemical sensor of tryptophan based on Ag C core-shell nanocomposite modified glassy carbon electrode. Anal. Chim. Acta 738 (2012)35-40. 

L. Yang, S. Liu, Q. Zhang, F. Li, Simultaneous electrochemical determination of dopamine and ascorbic acid using AuNPs polyaniline core-shell nanocomposites modified electrode, Talanta 89 (2012) 136-141. 

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