CdS nanoclusters

Lover T ef a/1997 Functionalization and capping of a CdS nanocluster a study of ligand exchange by electrospray mass spectrometry Chem. Mater. 9 1878... 

The intrinsic charge-generation efficiency of polymers is often low and needs to be enhanced by the addition of sensitizers. The sensitizer can be dissolved in the polymer to enhance the bulk charge-generation efficiency of the polymer. Effective sensitizers include 2,4,7-trinitro-9- uorenone [129-79-3] (TNF), hiUerene, thiapyryhum dye, CdS nanoclusters, etc (Table 3). Molecular stmctures of selected sensitizers are shown in Figure 8. 

Uosaki K, Okamura M, Ebina K (2004) Photophysical and photoelectrochemical characteristics of multilayers of CdS nanoclusters. Faraday Discuss 125 39-53... 

Curri ML, Agostiano A, Manna L, Della Monica M, Catalano M, Chiavarone L, Spag-nolo V, Lugara M (2000) Synthesis and characterization of CdS nanoclusters in a quarternary microemulsion The role of the cosurfactant. J Phys Chem B 104 8391-8397... 

Fig. 7 Anodic dissolution of STM-tip-induced Cd nanoclusters on Au(l 11). The first row (a-c) shows clusters obtained at potential of 50 mV, at (a) 50 ...

Mono- and multiparticulate CdS layers CdS Monoparticulate layers of dodecylbenzenesulfonic-acid-stabilized CdS nanoclusters were constructed, sequentially transferred to solid substrates by the LB technique, and characterized 95... 

The CdS nanoclusters and their loose aggregates were also found to be effective catalysts for the photoreduction of aromatic ketones and olefins in methanol using triethylamine as sacrificial electron donor, yielding alcohols and dihydro compounds, respectively [152]. The use of CdS nanoclusters seems to afford more selectivity than the commercially available CdS powders. 

Vossmeyer T et al 1994 CdS nanoclusters synthesis, characterization, size dependent oscillator strength, temperature shift of the exitonic transition energy and reversible absorbance shift J. Phys. Chem. 98 7665... 

PHOTOLUMINESCENCE STUDIES ON CdS NANOCLUSTERS FABRICATED IN LANGMUIR-BLODGETT FILMS... 

Figure 2. (a) PL spectra of LB films on silicon substrates before and after the H2S treatment. 1 - as-prepared film of cadmium behenate 2-4 - films containing 30, 40 and 80 monolayers of cadmium behenate, respectively, after the H2S treatment. The arrow indicates the position of the bulk CdS bandgap. (b) PL spectra of CdS nanoclusters fabricated in an 80 monolayer LB matrix. 1 - nanoclusters in the matrix, 2 - nanoclusters after removing the matrix by hexane, 3 - nanoclusters after removing the matrix by thermal annealing, 4 - approximation of the spectrum 1 by three Gaussian curves shown by dotted lines. 

Besides the fullerenes and the Fe clusters described above, other atomic clusters of small and intermediate sizes have been studied using SIESTA. Examples are Ni-C [274, 275] and Ni-Al [276] clusters, bare and passivated gold nanoclusters [276-282], aluminum oxide clusters [283], and Zn and Cd nanoclusters [284]. 

Pietro and coworkers [33, 34] have demonstrated that a wide scope of interesting molecular moieties can be covalently tethered onto the surface of CdS nanocrystals, and that the properties of the resulting systems depend to a great extent on the nature of the surface groups. They [35] have also demonstrated that 30 A thiolate-capped CdS nanoclusters photodecom-pose to form bulk CdS and a single organic product, the symmetric disulfide corresponding to the thiolate cap, and further... 

Fig. 8 Schematic illustration of binding of the CdS nanoclusters from reverse micelles onto gold via dithiol and the formation of alternating layer-by-layer structure (a) dithiol SAM on a gold substrate (Au-dt) (b) CdS nanoclusters attached on the SAM (Au-dt-CdS) ...

Fig. 9 Preparation procedures of CdS nanoclusters/PAH multilayers by the alternate two-step dip of the substrate into aqueous solutions containing CdS nanoclusters and PAH [111].

Semiconductor particles can also be used advantageously in coating applications to provide specific optical response to the material. As an example, Kumacheva et al. recently described the synthesis of monodisperse nanocomposite particles with inorganic CdS nanocrystals sandwiched between a PMMA core and a P(MMA-co-BA) outer copolymer shell layer. The particles are prepared by emulsion polymerization in three steps (Fig. 4.21) [144]. In a first step, polymer latexes are used as host matrices for CdS nanocrystals formation [145,146]. To do so, monodisperse poly(methyl methacrylate-co-methacrylic acid) (PMMA-PMAA) latex particles were ion-exchanged with a Cd(Cl04)2 solution. The Cd + ions thus introduced into the electrical double layer were further reduced into CdS nanoclusters by addition of a Na2S solution. The CdS-loaded nanocomposite particles were subsequently recov-... 

Wang, Y. and Herron, N. (1992). Photoconductivity of CdS nanocluster-doped polymers. Chem. Phys. Lett., 1992, 200, 71-75. 

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