Nanoparticle network

Bifunctional spacer molecules of different sizes have been used to construct nanoparticle networks formed via self-assembly of arrays of metal colloid particles prepared via reductive stabilization [88,309,310]. A combination of physical methods such as TEM, XAS, ASAXS, metastable impact electron spectroscopy (MIES), and ultraviolet photoelectron spectroscopy (UPS) has revealed that the particles are interlinked through rigid spacer molecules with proton-active functional groups to bind at the active aluminium-carbon sites in the metal-organic protecting shells [88]. 

Mucic, R.C., Storhoff, J.J., Mirkin, C.A. and Letsinger, R.L. (1998) DNA-directed synthesis of binary nanoparticle network materials. Journal of the American Chemical Society, 120, 12674-12675. 

Several types of palladium-based hydrogen sensors have been reported in the literature. The most notable ones are based on Pd thin-film resistors, FETs, Pd nanowires, Pd nanoparticle networks, Pd nanoclusters, and Pd nanotubes as shown in Table 15.2. 

Schematic representation of the operation of the nanoparticle network hydrogen sensor.

Matsuda K, Yamaguchi H, Sakano T, Ikeda M, Tanifuji N, Irie M (2008) Conductance photoswitching of diarylethene gold nanoparticle network induced by photochromic reaction. J Phys Chem C 112(43) 17005-17010... 

Chen, S., Two-dimensional crosslinked nanoparticle networks, Adv. Mater., 12, 186, 2000. 

Willner and coworkers demonstrated three-dimensional networks of Au, Ag, and mixed composites of Au and Ag nanoparticles assembled on a conductive (indium-doped tin oxide) glass support by stepwise LbL assembly with A,A -bis(2-aminoethyl)-4,4 -bipyridinium as a redox-active cross-linker.8 37 The electrostatic attraction between the amino-bifunctional cross-linker and the citrate-protected metal particles led to the assembly of a multilayered composite nanoparticle network. The surface coverage of the metal nanoparticles and bipyridinium units associated with the Au nanoparticle assembly increased almost linearly upon the formation of the three-dimensional (3D) network. A coulometric analysis indicated an electroactive 3D nanoparticle array, implying that electron transport through the nanoparticles is feasible. A similar multilayered nanoparticle network was later used in a study on a sensor application by using bis-bipyridinium cyclophane as a cross-linker for Au nanoparticles and as a molecular receptor for rr-donor substrates.8... 

Due to the small size, nanoparticles are often used as building blocks in designing large assemblies and coreshell nanoparticle networks with various functionalities. Refs. [i] Templeton AC, Murray RW (2000) Acc Chem Res 33 27 [ii] Hepel M, Hazelton S (2005) Electrochim Acta 50 5278 [Hi] Luo J, Maye MM, Lou Y, Han L, Hepel M, Zhong C/ (2002) Catalysis Today 77 127... 

G. Schmid, M. Baumle, and N. Beyer, Ordered two-dimensional monolayers of AU53 clusters, Angew. Chem. Int. Ed. 39 181 (2000) S. Chen, Two-dimensional crosslinked nanoparticle networks, Ac v. Mater. 12 186 (2000) S. Sun, C.B. Murray, D. Weller, L. Folks, and A. Moser, Monodisperse FePt nanoparticles and ferromagnetic FePt nanocrystal superlattices. Science 287 1989 (2000) C.L. Bowes and G.A. Ozin, Self-assembling frameworks beyond microporous oxides, Adv. Mater. 8 13 (1996). 

Cigang, X., Harm van, Z., et al. A combined top-down bottom-up approach for introducing nanoparticle networks into nanoelectrode gaps. Nanotechnology,17(14), 3333 (2006). Clark, L. C. Monitor and control of blood and tissue oxygen tensions. Transactions American, Society for Artificial Internal Organs,2(1956). 

Figure 17 Idealized mechanism for the DNA-mediated formation of binary nanoparticle networks (a b). TEM images of the binary DNAHinked network as an assembly formed from 8 and 30 nm gold colloids (c). Reprinted with permission from Mirkin, C. A. Inorg. Chem. 2000,39,2258 and Mucic, R. C. Storhoff, J. J. Mirkin, C. A. Letsinger, R. L. J. Am. Chem. Soc. 1998, 120,12674. Copyright 2000 and 1998, American Chemical Society. - ...

Tetraethoxyorthosilane and linseed oil polyol silica embedded polyurethane nanocomposites were obtained by a sol-gel technique. The polyol/ silica nanoparticles network showed a strong interaction with uniform, spherical silica nanoparticles of 2-30 nm size embedded in the polymer matrix. The system was further reinforced by 2 wt% and 5 wt% fumed silica. The resultant systems showed improved thermal stability with mild to moderate antibacterial behaviour against E. coli and S. aureus. 

M. Ikeda, N. Tanifuji, H. Yamaguchi, M. Me, K. Matsuda, Photoswitching of conductance of diarylethene-Au nanoparticle network, Chem. Commun., 1355-1357 (2007). 

Leventis N, Chandrasekaran N, Sadekar A G, Mulik S, Sotiriou-Leventis C (2010) The effect of compacmess on the carbothermal conversion of interpenetrating metal oxide/resorcinol-formaldehyde nanoparticle networks to porous metals and carbides. J Mater Chem 20 7456-7471... 

Arachchige lU, Mohanan JL, Brock SL (2005) Sol-gel processing of semiconducting metal chalcogenide xerogels Influence of dimensionality on quantum confinement effects in a nanoparticle network. Chem Mater 17 6644-6650... 

Crystalline Nanoparticle Networks as Templates A third method for fabricating 3D conductive polymer networks is by the immobilization of crystalline nanoparticles onto working electrodes followed by the electrodeposition of CP. While no nanowires/nanotubes are fabricated, this technique leads to CP structures with high surface area and permeability. Figure 13.4 shows a basic representation for this process. 

Zheng WX, Maye MM, Leibowitz FL, Zhong CJ (2000) Imparting biomimetic ion-gating recognition properties to electrodes with a hydrogen-bonding structured core-shell nanoparticle network. Anal Chem 72 2190-2199... 

Kashiwagi T, Du F, Douglas J F, Winey K I, Harris R H and Shields J R (2005) Nanoparticle networks reduce the flammability of polymer nanocomposites, Nat Mater 4 928-933. 

Figure 17 TEM images of gold nanoparticle networks formed using the belt-and-braces peptides, (a) A 2D network (b) a 3D network. (Reproduced from Ref. 72. American Chemical Society, 2003.)...

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