Experimental Formation and Mechanism Study for Super-High Dielectric Constant AlO/TiO Nanolaminates.

Super-high dielectric constant () AlO/TiO nanolaminates (ATO NLs) are deposited by an atomic layer deposition technique for application in next-generation electronics. Individual multilayers with uniform thicknesses are formed for the ATO NLs. With an increase in AlO content in each ATO sublayer, the shape of the Raman spectrum has a tendency to approach that of a single AlO layer.

Ultrafast dynamics of photogenerated electrons in CdS nanocluster multilayers assembled on solid substrates: effects of assembly and electrode potential.

The ultrafast dynamics of photogenerated electrons in multilayer assemblies of CdS nanoparticles prepared on quartz and indium-tin oxide (ITO) substrates were followed by femtosecond (fs) visible-pump/mid-IR probe spectroscopy. Based on the observation of the photoinduced transient absorption spectra in the broad mid-IR range at the multilayer assembly of CdS nanoparticles, the occupation and fast relaxation of higher electronic states (1P(e)) were clarified. As compared with the electron dynamics of isolated (dispersed in solution) nanoparticles, the decay of photoexcited electrons in the multilayer assembly was clearly accelerated probably due to both electron hopping and scattering during interparticle electron tunneling.

Size-dependent carrier dynamics in CdS nanoparticles by femtosecond visible-pump/IR-probe measurements.

Ultrafast photoexcited carrier dynamics in CdS nanoparticles prepared by an AOT/n-heptane reversed micelle system were investigated by a femtosecond visible-pump/mid-IR probe technique. A mid-IR probe beam was found to mainly probe the ultrafast dynamics of photoexcited electrons in the conduction band. Dispersions of CdS nanoparticles with 8 different mean diameters from 2.

Electrochemical assembly and potential-dependent plasmon absorption of au nanoclusters covered with a 4-aminothiophenol self-assembled monolayer.

Gold nanoclusters covered with 4-aminothiophenol (4-ATP) self-assembled monolayers (SAMs) were electrochemically assembled on an Au or ITO electrode. The assembly mechanism is discussed on the basis of results of electrochemical, FT-IR, and XPS measurements. The intensity of plasmon absorption of the gold nanocluster assembly was shown to be dependent on applied potential as a result of electrochemical doping/undoping of a counteranion in the polyaniline film.

Photophysical and photoelectrochemical characteristics of multilayers of CdS nanoclusters.

Luminescence lifetime measurements in sub-ns time resolution and visible pump-IR absorption probe measurements to study photo-induced carrier dynamics using fs laser pulses were carried out for the CdS nanoclusters prepared by reverse micelle method, the nanoclusters modified with 2-mercaptoethanesulfonate (SO3-CdS) in water, and the SO3-CdS nanoclusters in a multilayer assembly. For a comparison, similar measurements were also carried out for a CdS nanocluster doped glass. The photoelectrochemical characteristics of the multilayer are also measured.

Electron and ion transfer through multilayers of gold nanoclusters covered by self-assembled monolayers of alkylthiols with various functional groups.

The electrochemical characteristics of various kinds of multilayers of gold nanoclusters (GNCs) were investigated. Two types of gold nanoclusters, one covered by self-assembled monolayers (SAMs) of mercaptoundecanoic acid (MUA), hexanethiol (C6SH), and ferrocenylhexanethiol (FcC6SH), MHF-GNC, and the other with MUA and C6SH, MH-GNC, were used. The multilayers were constructed on a Au(111) surface based on a carboxylate/metal cation (Cu++)/carboxylate or carboxylate/cationic polymer (poly(allylamine hydrochloride):PAH)/carboxylate electrostatic interaction.