Nanostructures nanostructured membranes

A promising application of the self-assembly of nanoparticles at droplet surfaces is the interfacial crosslinking of chemically functionalized nanoparticles. This enables the encapsulation of water-soluble or oil-soluble materials inside the resulting nanocontainers. By varying the concentration of reactive moieties, it will be possible to control the permeability and strength of these nanostructured membranes. 

Michel M, Taylor A, Sekol R, Podsiadlo P, Ho P, Kotov N, Thompson L, et al. (2(X)7) High-performance nanostructured membrane electrode assemblies for fuel cells made by layer-by-layer assembly of carbon nanocoUoids. Adv. Mater. 19 3859—3864. 

Thiam HS, Daud WRW, Kamarudin SK, Mohammad AB, Kadhum AAH, Loh KS, Majlan EH (2011) Overview on nanostructured membrane in fuel cell applications. Int J Hydrogen Energ 36 3187-3205... 

Crespilho, F.N., Ghica, M.E., Gouveia-Caridade, C., Oliveira, Jr., O.N., Brett, C.M.A. Enzyme immobilization on electroactive nanostructured membranes (ENM) Optimised architectures for biosensing. Talanta 76, 922-928 (2008)... 

E.H. (2011) Overview on nanostructured membrane in fuel cell applications. 

Tsuchiya M, Lai BK, Ramanathan S (2011) Scalable nanostructured membranes for solid oxide fuel cells. Nat Nanotechnol 6 282-286... 

In a distinct vein, BC/chitosan membranes have been tested for pervaporative separation of binary aqueous-organic mixtures (ethanol/water) [111]. The substantially high pervaporative separation index (350 kg. x.m. h 0 and low activation energy (10 kj.mol ) are indicative of the high potential of BC/chitosan membranes in the pervaporative separation of ethanol/water azeotrope. Targeting to mimic the intrinsic antimicrobial properties of chitosan on BC nanofibrils, nanostructured BC nanocomposite membranes were obtained by surface functionalization with aminoalkyl groups (Figure 2.14) [114]. These bioactive nanostructured membranes also presented improved mechanical and thermal properties and may be useful for biomedical applications. 

M. Michel, F. Ettingshausen, F. Scheiba, A. Wolz, C. Roth, Using layer-by-layer assembly of polyaniKne fibers in the fast preparation of high performance fuel cell nanostructured membrane electrodes, Phys. Chem. Chem. Phys. 10 (2008) 3796. 

Aparicio, M., Mosa, J., and Duran, A. (2006) Hybrid organic-inorganic nanostructured membranes for high-temperature proton exchange membrane fuel cells (PEMFC). J. Sol-Gel Sci. TechnoL, 40, 309-315. 

Freeman [55] reported on nanostructured membrane materials for gas separation applications and presented examples where the incorporation of nanoscale particles into rigid polymers enhances the permeability and selectivity, for certain separations, based primarily on the disruption of the polymer chain packing by the nanoparticles (i.e., by altering diffusion selectivity of the polymer matrix). In addition, they discussed the incorporation into polymers of nanoparticles with specific interactions with particular gases (e.g., CO ) as a route to increase permeability and selectivity by altering the diffusion selectivity and solubility selectivity. 

Di Noto V, Negro E, Sanchez J-Y, lojoiu C (2010) Structure-relaxation interplay of a new nanostructured membrane based on tetraethylammonium trifluoromethanesulfonate ionic liquid and neutralized nation 117 for high-temperature fuel cells. J Am Chem Soc 132(7) 2183-2195. doi 10.1021/ja906975z... 

Thielemans W, Warbey CR, Walsh DA (2009) Permselective nanostructured membranes based on cellulose nanowhiskers. Green Chem 11(4) 531—537... 

PGMs such as Pt and Pd (Figs 11.5 and 11.6). The membranes developed have been tested with various reactions, such as in proton exchange membrane (PEM) fuel cells and in hydrocarbon hydrogenation (e.g., Halonen et al, 2010 Job et al., 2009 Stair et al., 2006). The nanostructured membrane AAO framework studied by Stair et al. (2006) is presented in Fig. 11.6. A similar type of a framework has been used also with the CNT support framework (Kordas et al, 2006). This kind of a structure provides more uniform contact time and controlled reagent flow, as well as decreased sintering phenomena (Stair et al, 2006). By designing new catalyst systems by... 

A question of practical interest is the amount of electrolyte adsorbed into nanostructures and how this depends on various surface and solution parameters. The equilibrium concentration of ions inside porous structures will affect the applications, such as ion exchange resins and membranes, containment of nuclear wastes [67], and battery materials [68]. Experimental studies of electrosorption studies on a single planar electrode were reported [69]. Studies on porous structures are difficult, since most structures are ill defined with a wide distribution of pore sizes and surface charges. Only rough estimates of the average number of fixed charges and pore sizes were reported [70-73]. Molecular simulations of nonelectrolyte adsorption into nanopores were widely reported [58]. The confinement effect can lead to abnormalities of lowered critical points and compressed two-phase envelope [74]. 

Chapter 15 gives an extensive and detailed review of theoretical and practical aspects of macromolecular transport in nanostructured media. Chapter 16 examines the change in transport properties of electrolytes confmed in nanostructures, such as pores of membranes. The confinment effect is also analyzed by molecular dynamic simulation. 

Thin film nanostructures of the III-VI compound In2Se3 were obtained inside the pores (200 nm) of commercial polycarbonate membrane by automated ECALE methodology at room temperature [157], Buffered solutions with millimolar concentrations of In2(S04)3 (pH 3.0) and Se02 (pH 5.5) were used. The atomic ratio of Se/In in the deposited films was found to be 3/2. Band gaps from FTIR reflection absorption measurements were found to be 1.73 eV. AFM imaging showed that the deposits consist of 100 nm crystallites. 

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