Optical nanocomposite films

Fig. 1.12 (A) Increase in surface plasmon ab- and from mixtures with lower chitosan concen-sorptionasAu nanoparticles are produced from a tration (ii) or lower HAuCI4 amount (iii) six reaction mixture containing 1 % chitosan, 1 % different self-sustained nanocomposite films acetic acid and 0.01 % tetrachloroauric (III) acid showing the control over the optical properties. (HAuCU) (B) shiftofsurface plasmon absorption Reprinted with permission from [164], 2004, for films prepared from the previous mixture (i), American Chemical Society.

Hence, finite size effects on the optical response of metal nanoparticles are very difficult to take into account in an accurate manner. Moreover, in most experiments carried out on thin nanocomposite films or colloidal solutions the particle size distribution is not mono-dispersed but more or less broad, that can be usually determined by analysis of transmission electronic microscopy images. It should be underlined that the relevant quantity for smdying size effects in the optical response of such media can definitely not be the mean cluster radius , although it is often used in the literature [28-33], since the contribution of one nanoparticle to the optical response of the whole medium is proportional to its volume, i.e. to (cf. Eq. 7). The relevant quantity, that we call the optical mean radius , would then rather be the third-order momentum of the size distribution, = / ... 

C. Structural and optical properties of CiKsiUca nanocomposite films prepared by co-sputtering deposition. Appl. Surf. Sci. 226. 52-56 (2004)... 

Serna, R., Ballesteros, J.M., Solis, J., Afonso, C.N.. Osborne, D.H., Haglund, Jr., R.F., Petford-Long, A.K. Laser-induced modification of the nonlinear optical response of laser-deposited CuiALO, nanocomposite films. Thin Sol. Films 318. 96-99 (1998)... 

Yang, G., Wang, W.-T., Yang. G.-Z., Chen, Z.-H. Enhanced nonlinear optical properties of laser deposited Ag/BaTiO3 nanocomposite films. Chin. Phys. Lett. 20, 924-927 (2003)... 

Raman spectra showed that the diamond phonon line broadening started to show up even at 5 seem of TMS flow rate indicating the influence of increasing P-SiC Volume% in the films with an increase in TMS flow rate. FTIR measurements illustrated that greater transverse optic phonon (TO) band intensity obtained from the samples deposited with greater TMS concentration showed qualitatively the presence of laiger volume of p-SiC in the films. As an example, FTIR speara obtained from two different diamond/p-SiC nanocomposite films deposited on W substrates are shown in Fig. 3. Additionally, quantitative compositional analysis (RBS measurements EPMA) showed that the content of p-SiC in the films corresponds almost linearly to the TMS concentration in the gas phase during the film deposition. 

Figure 3. (a) IR spectra obtained from two diamond/p-SiC nanocomposite films deposited on W substrates by using different TMS flow rates. The transverse optical phonon band around 800 cm corresponds to the presence of p-SiC. (b) Backscattered electron cross-sectional micrograph of a gradient natured diamond/p-SiC nanocomposite film deposited on BEN pre-treated (100) Si substrate. The bright spots indicate p-SiC phase. 

Koshizaki N., Yasumoto K., and Sasaki T., Mechanism of optical transmittance change by NOj in CoO/Si02 nanocomposites films. Sens. Actuators B, 66, 122-124, 2000. 

In Fig. 13.18, the normalized eurrent ratio of Brij 56-templated TSUA-modified nanocomposite films is 40%. However, in another experiment using P123-templated films that have a larger pore size (ca. 6.5 nm), the normalized current ratio is only 1.2%. Because the molecular length of azobenzene ligands located on the pore surfaces is 1.8 and 1.5 nm in the trans and cis forms, respectively, the optically triggered restriction in pore size is expected to have a diminished effect on transport for P123-templated films compared with the smaller pore size Brij 56-templated films. 

J. Perez-Juste, B. Rodriguez-Gonzalez, P. Mulvaney, L.M. Liz-Marzan, Optical control and patterning of gold-nanorod-poly(vinyl alcohol) nanocomposite films. Adv. Funct. Mater. 15,... 

Figure 7.13 Absorption spectra of [a] PEDOT-RGO and (b) PEDOT-ILFG nanocomposite Aims recorded under different dc potentials in the IL. Change in optical density versus inserted charge density plots for [c) PEDOT-RGO and [d] PEDOT-ILFG nanocomposite films at a monochromatic wavelength of 550 nm. Insets of (c) and (d) are the same films in dark [-2.0 V] and pale (+1.0 blue states. Reprinted with permission from Ref. [99]. Copyright 2011, American Chemical Society.

The ECP/CNM nanocomposites are mainly used as counter electrodes in solar cells like dye-sensitized solar cells, for example, PEDOT PSS/ graphene nanocomposite film electrodes [81]. The optical transparency and the high conductivity of these nanocomposite films have increased... 

Polymeric ZnO nanocomposite materials have attracted global interest because introduction of ZnO filler into polymeric matrices can modify the optical (e.g., shielding from UV and NIR radiation), electrical and mechanical properties. Investigations have been made regarding the optical properties of spin-coated, highly transparent nanocomposite films of oleic acid modified ZnO (Zinc oxide) nanorods embedded in Polyvinyl alcohol (PVA) matrix. Pristine and oleic acid (OA) modified ZnO nanorods... 

FIGURE 8.3 Representative optical micrographs (OM) of batch-mixed nanocomposite films (7-12 pm thick) at 20 wt% (a) PR-19 HT, (b) PR-19 HT-Sonicated (c) MWNT HT and (d) MWNT HT-Sonicated. Insets display the microstructure at higher magnification. 

Pinto RJ, Fernandes SC, Freire CS, Sadocco P, Causio J, Neto CP, Trindade T. Antibacterial activity of optically transparent nanocomposite films based on chitosan or its derivatives and silver nanoparticles. Carbohydr Res. 2012 348 77-83. 

In the present chapter, we report the synthesis of ZnS nanocrystals and ZnS/PVA nanocomposite films, their structural and optical characterization and photo- as well as electro-luminescence investigations. 

Fig. 4.4 (a) Schematic of Pd-based optical sensor and (b) calibration curve of a 40-nm thick Pd-polymer nanocomposite film at 370 nm (Reprinted with permission from Fedtke et al. (2004). Copyright 2004 Elsevier)... 

Figure 12.9 Optical microscopy (top) and atomic force microscopy (bottom) images of a scratched polymer/CNC nanocomposite film containing UI -functionalized CNCs before (left), during (middle), and after (right) exposure to UV irradiation that results in the healing of the material. Reprinted with permission from M. V. Biyani, E. J. Foster and C. Weder, ACS Macro Lett., 2013, 2, 236-240, Copyright 2013 American Chemical Society.

CNF, and good optical transparency. As typical biopackaging, a thin transparent film was formed. Starch/chitosan nanocomposite film (S C 9 1+2 %CNF) that incorporated with CNF showed less translucent than starch/chitosan composite film (S C 9 1) but stiU relatively adequate to be classify as good packaging film. This may due to the good dispersion of CNF in the composite film. The composite film that incorporated with CNF also represents more tough structure and easy to handle where composite film without incorporation of CNF was easy to break when peeled off from the casting space. 

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