Nanomorphology

The model, therefore, predicts the elution behavior of solutes during a chromatographic process over a swollen gel as the stationary phase as a function of solute size and of the gel nanomorphology. On the reverse, from the elution behavior of solutes of known molecular size it is possible to extract the polymer chain concentration from chromatographic experiments, where an unknown swollen gel is the stationary phase. This is the basis of the ISEC, which is so often mentioned through this chapter [16,17,105,106]. 

To the best of our knowledge, such a control of nanocluster size through the nanomorphology of the stabilizer cannot be achieved with any other system, not even with those in which the metal nanocluster precursors are physically confined within nanometer-sized cavities [23]. 

Schmidt, M. W. I., Skjemstad, J. O., and Jager, C. (2002). Carbon isotope geochemistry and nanomorphology of soil black carbon Black chernozemic soils in central Europe originate from ancient biomass burning, Global Biogeochem. Cycles 16, Art. No. 1123. 

Biffis A, Orlandi N, Corain B (2003) Microgel-stabilised metal nanoclusters size control by microgel nanomorphology. Adv Mater 15 1551-1555... 

One can make two remarks. Firstly, the 7 value of initial goethite (FeOOH) is rather high, too high compared to the mean 7 values of oxides. Secondly, the evolution of 7 does not exactly correlate with the departure of water. Therefore, it seems reasonable to suspect that the change of 7 is ascribable to chemical alteration of the surface upon heating, but also to some other factor, probably a change of nanostructure or nanomorphology as we shall discuss it afterwards. 

Of course, we do not expect to detect the same behaviours of diols on precipitated silicas that present rather rough surfaces as can be shown using a fractality approach [16] i.e., estimating the surface nanomorphology by the small angle X-ray diffraction or interpreting adsorption isotherms of a homologous series of adsorbents. The main conclusion of this part of our study is that ... 

In the previous equation, there are two unknown quantities the values of the equilibrium constants and the true values of the accessible areas. K and are dependent on the polarisabilities of linear and branched alkanes that are not identical. But, their ratio can be measured on the reference silica, as well as the ratio of the actual contact areas. Consequently, the index of nanomorphology, Im, will be defined by ... 

Specific surface area (S), dispersive component (7 ) of the surface energy and nanomorphology index ( ,) of a variety of divided solids at 80°C... 

Figure 9. Variation of 7 with respect to the nanomorphology index ( ,) of 2,5-dimethylhexane (O), 2,2,4-trimethylpentane ( ), 2,3,4-trimethylpentane ( ), 2,2,4,4-tetramethylbutane ( ).

Chirvase D., Parisi J., Hummelen J. C. and Dyakonov V. (2004), Influence of nanomorphology on the photovoltaic action of polymer-fullerene composites , Nanotechnology 15, 1317-1323. 

Drees M., Hoppe H., Winder C., Neugebauer H., Sariciftci N. S., Schwinger W., Schaffler F., Topf C., Scharber M. C., Zhu Z. G. and Gaudiana R. (2005), Stabilization of the nanomorphology of polymer-fullerene bulk heterojunction blends using a novel polymerizable fullerene derivative , J. Mat. Chem. 15, 5158-5163. 

Within the bulk heterojimction, the donor and acceptor domains are generally disordered in volume. For exciton dissociation and charge generation a fine nanoscale intermixing is required, whereas for the efficient transport of charge carriers percolation and a certain phase separation are needed to ensure imdisturbed transport. Hence the optimization of the nanomorphology of the photoactive blend is a key issue for improving the efficiency of the photovoltaic operation [62,66,67]. 

Another influence on oc may arise from aluminum electrodes, which can form a thin oxide layer at the interface to the organic materials [84,115,116], resulting in possible changes in the effective work function. A dependence of the Voc on the nanomorphology arising from the fullerene content in bulk heterojunction blends was also observed [55,117-121] and proposed to originate from the partial coverage of the cathode by fullerenes [118]. 

A comprehensive discussion on the nanomorphology of polymer blends based on TFB F8BT and PFB F8BT, as used for polymer light-emitting diodes and polymer solar cells, respectively, is presented in [66,67]. Kim et al. considered the ternary phase diagram, comprised of the two polymers and the... 

Gel-type, microporous, resins must swell to expose their catalytically active sites, whereas macroreticular resins have a permanent pore structure (inside these pores, catalytically active sites reside). Pores of the macroreticular resins can be described acceptably in terms of the conventional cylindrical pore model (pore diameter and volume). Pore structure, size, pore volume, and so on have been studied intensively in recent years. Examples of analytical techniques include X-ray microprobe analysis, ESR spectroscopy, NMR, and inverse steric exclusion chromatography (ISEC) the latter yields the best quantitative assessment of the nanomorphology of swollen resins. 

The most commonly studied polymer nanocomposites are clay-based nanocomposites, mainly with montmorillonite (MMt) as layered silicate filler (Scheme 15.12). Upon incorporation of organomodihed clays (organoclays) into a polymer matrix, two nanomorphologies (Scheme 15.13) can be obtained, either intercalation of the polymer chain in between the clay platelets keeping the stacking of the sheets, or exfoliation of the clay platelets with a disordered dispersion of the inorganic sheets in the polymer. 

Performance Enhancement and Nanomorphology Control in Polymer Solar Cells... 

In the following sections, we will discuss and compare the effect of two approaches on absorption, polymer crystallinity, nanomorphology, I-V characteristics, charge carrier mobility, and exciton generation and dissociation. 

We have shown nanomorphology of the composite layer strongly influences the BHJphotovoltaic performanceinRR-P3HT PCBMsystem. This is also truefor the low band-gap polymer system when C70-PCBM is used. Because C70-PCBM... 

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