Nanoparticle arrays

Lamm MS, Sharma N, Rajagopal K et al (2008) Laterally spaced linear nanoparticle arrays templated by laminated beta-sheet fibrils. Adv Mater 20 447M 51... 

Sharma N, Top A, Kiick KL et al (2009) One-dimensional gold nanoparticle arrays by electrostatically directed organization using polypeptide self-assembly. Angew Chem Int Ed 48 7078-7082... 

Summing up this section, we would like to note that understanding size effects in electrocatalysis requires the application of appropriate model systems that on the one hand represent the intrinsic properties of supported metal nanoparticles, such as small size and interaction with their support, and on the other allow straightforward separation between kinetic, ohmic, and mass transport (internal and external) losses and control of readsorption effects. This requirement is met, for example, by metal particles and nanoparticle arrays on flat nonporous supports. Their investigation allows unambiguous access to reaction kinetics and control of catalyst structure. However, in order to understand how catalysts will behave in the fuel cell environment, these studies must be complemented with GDE and MEA tests to account for the presence of aqueous electrolyte in model experiments. 

Interpretation of pubhshed data is often comphcated by the fact that rather complex catalytic materials are utilized, namely, poly disperse nonuniform metal particles, highly porous supports, etc., where various secondary effects may influence or even submerge PSEs. These include mass transport and discrete particle distribution effects in porous layers, as confirmed by Gloaguen, Antoine, and co-workers [Gloaguen et al., 1994, 1998 Antoine et al., 1998], and diffusion-readsorption effects, as shown by Jusys and co-workers for the MOR and by Chen and Kucemak for the ORR [Jusys et al., 2003 Chen and Kucemak, 2004a, b]. Novel approaches to the design of ordered nanoparticle arrays where nanoparticle size and interparticle distances can be varied independently are expected to shed hght on PSEs in complex multistep multielectron processes such as the MOR and the ORR. 

A. Haryono and W. H. Binder, Controlled arrangement of nanoparticle arrays in block-copolymer domains, Small, 2006, 2, 600. 

Ohara, P.C. and Gelbart, W.M. (1998) Interplay between hole instability and nanoparticle array formation in ultrathin liquid films. Langmuir, 14 (12), 3418-3424. 

Owing to their unique (tunable-electronic) properties, semiconductor (quantum dots) nanocrystals have generated considerable interest for optical DNA detection [12], Recent activity has demonstrated the utility of quantum dot nanoparticles for enhanced electrical DNA detection [33, 34, 50], Willner et al. reported on a photoelectrochemical transduction of DNA sensing events in connection with DNA cross-linked CdS nanoparticle arrays [50], The electrostatic binding of the Ru(NH3)63+ electron acceptor to the dsDNA... 

I. Willner, P. Patolsky, and J. Wasserman, Photoelectrochemistry with controlled DNA-cross-linked CdS nanoparticle arrays. Angew. Chem. Int. Ed. 40, 1861-1864 (2001). 

A.N. Shipway, E. Katz, and I. Willner, Nanoparticle arrays on surfaces for electronic, optical and senso-ric applications. Chemphyschem 1, 18-52 (2000). 

Figure 14.7. Left Solution-processed quantum dot structure of InP nanoparticles (black dots) in a Ti02 nanoparticle array (open circles). The QDs could sensitize an optical response similar to the dye in a Gratzel cell. Right A schematic of very small QDs (balls) bonded to a controlling surfactant that is bonded to a surface specific element, such as a TCO surface.

Diez I, Hahn H, Ikkala O, Bomer HG, Ras RHA (2010) Controlled growth of silver nanoparticle arrays guided by a self-assembled polymer-peptide conjugate. Soft Matter 6 3160-3162... 

Synthesis ofPt and Au Nanoparticle Arrays in Mesoporous Silica Films 631... 

Synthesis ofPt and Au Nanoparticle Arrays in Mesoporous Silica Films and their Electric/Magnetic Properties in Terms of the Quantum-Size Effect... 

Figure 15.28 TEM images of (a) Au nanoparticle arrays in mesoporous silica film (b) superlattice of extracted Au nanoparticles stabilized with 1-dodecanethiol.

From above experimental results, Pt nanoparticle arrays were similarly formed in the mesoporous silica film by the photoreduction of H2PtCl6/mesoporous silica film/Si in the presence of vapors of water and methanol. As shown in Figure 15.29, Pt nanoparticles (diameter 3 nm) are packed close to each other in the one-dimensional mesopores, and in some part the arrays of Pt nanoparticles show an ordered structure [27]. 

Self-assembly of nanoparticles in well-ordered 2-D arrays represents a major goal in the fabrication of microelectronics devices (Sun et al. 2002, 2003). Different strategies have been developed to tackle the challenge of well-organized nanoparticles in a 2-D plate surface (Andres et al. 1996 Spatz et al. 2000). Schmid and coworkers (2000) reported a long-range ordered sulfonic acid functionalized nanoparticle array... 

The formation of a patterned surface through selective segregation of nanoparticles onto one domain of a block copolymer film can be used to produce complex 2-D nanoparticle arrays in a controlled fashion. However, the resulting... 

Farrell D, Cheng Y, Ding Y, Yamamuro S, Sanchez-Hanke C, Kao C-C, Majetich SA. Dipolar interactions and structural coherence in iron nanoparticle arrays. J Magn Magn Mater 2004 282 1-5. 

Novak JP, Nickerson C, Franzen S, Feldheim DL (2001) Purification of molecularly bridged metal nanoparticle arrays by centrifugation and size exclusion chromatography. Anal Chem 73 5758-5761... 

Raj CR, Okajima T, Ohsaka T (2003) Gold nanoparticle arrays for the voltammetric sensing of dopamine. J Electroanal Chem 543 127-133... 

McConnell WP et al. (2000) Electronic and Optical Properties of Chemically Modified Metal Nanoparticles and Molecularly Bridged Nanoparticle Arrays. J Phys Chem B 104 8925-8930... 

Jiang C, Singamaneni S, Merrick E, Tsukruk VV (2006) Complex buckling instability patterns of nanomembranes with encapsulated gold nanoparticle arrays. Nano Lett 6 2254-2259... 

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