Subject nanostructured materials

In Chapter 24, Duo and coworkers discuss metal oxide nanoparticle reactivity on synthetic boron-doped diamond surfaces. Lamy and Leger treat electrocatalysis with electron-conducting polymers in the presence of noble metal nanoparticles, and new nanostructure materials for electrocatalysis are the subject of the final chapter, by Alonso-Vante. 

The electrodeposition of nanostructured materials from LLC phases is not restricted to noble metals, but can be extended into the field of semiconductors [69]. Mesoporous regular semiconductors have great potential for applications in optical sensors and solar cells. The successful electrodeposition of selenium was demonstrated by Nandhakumar et al., who subjected a hexagonally struc-... 

This monograph started out simply as a paper presented at the Osaka University Macromolecular Symposium in Osaka (November 5-7, 2001). Because of the great strides made recently in nanoscience, it was considered appropriate to expand this paper into a complete book. Some of the concepts based on nanostructured material science have stimulated the main subjects of the 21st Century COE... 

Nanostructured materials are a subject of growing interest in catalysis since they are expected to exhibit enhanced catalytic reactivity when compared to conventional materials [6]. We have previously used a counterflow diffusion flame burner to produce and study the formation of nanostructured oxides and mixed oxides [7][8]. 

Apart from these properties, the exeellent barrier eapability to moisture and gases of polymeric nanocomposites has shown significant potential in civil engineering applications [34—36]. It was reported that the construction industry will be one of the major potential consumers of nanostructured materials [37]. A substantial decrease in moisture permeability was reported in polyamide nanoclay composites with water absorption rate reduced by 40% in comparison to neat polymer [38]. An 80% decrease in water absorption was reported for poly (e-caprolactone) nanoclay composites [39]. Hackman and Hollaway studied the potential appheations of clay nanocomposite materials to civil engineering structures. They eoncluded that their ability to increase the service life of materials subjected to aggressive environments could be utilized to increase the durability of glass and carbon fiber composites [34]. 

A way to see the importance that is given to nanostructured materials synthesis processes is to consult the historical of article publishing concerning this subject. Indeed, based on Fig. 1.1, which presents a survey about nanoparticles or nanoma-terials synthesis processes, it is possible to observe a yearly increment of number of papers published on this subject. For example, in 2012 only, over 19,000 papers were available in the international literature regarding the synthesis of nanomaterials. It is circa 18 % more than the year before and over nine times more than 2003. Up to July 2013, the impressive number of 20,925 papers were already published about this same subject... 

The production of nanostructured carbon materials by hydrothermal processes from natural precursors is one of the most attractive subjects in material science today. Carbon materials prepared from hydrothermal process are currently being used in various fields of research including environmental, electrical, chemical, and biomedical fields. In environmental application, carbon is mainly used as a sorbent material for the removal of heavy metal ions (CrO/, Pb +, and Cd +) from water and wastewater [116,117]. Carbon nanocoils prepared from saccharides (sucrose, glucose, and starch) with a support of Pt/Ru nanoparticles exhibit a high catalytic activity for the electro-oxidation of methanol in an acid medium [150]. Similarly, electro-oxidation of ethanol and methanol was carried out with electro catalysts, such as Pd/CHC (coin-like hollow carbon), Pt/ HCS (hard carbon spherules), and Pt/Pd/CMS (carbon microspheres) in acidic and alkaline media... 

This chapter focuses on polyferrocenylsilanes (PFSs) where iron and silicon are in the main chain. Subsequently, PFS block copolymers will be reviewed. These materials represent an area of rapidly growing interest as a result of their self-assembly into phase-separated metal-rich nanodomain structures in thin films and micelles in block-selective solvents. The resulting nanostructured materials have a wealth of potential applications and recent breakthroughs in this area are discussed. The subject matter of the chapter is divided up into subsections covering PFS homopolymer and block copolymer synthesis, solution and solid-state self-assembly and applications of the latter, which have been extensively developed by ourselves and our collaborators and also by other research groups. 

The kinetics of diffusion occurring in nanostructured materials is a subject of intensive study [178,179]. Materials at the nanoscale showed sharp acceleration of diffusion [180], indicating the lowered activation energy of diffusion. The activation enthalpies for the interfacial diffusion are comparable to those for surface diffusion, which are much lower than those for diffusion along grain boundaries [181, 182]. 

The synthesis of silicone nanoparticles is a very interesting research subject. The materials of this kind have found widespread industrial and technological applications. The nanostructural silicone nanospheres have been shown to be promising supports for catalysts in the production of the new tracer particles, and they might be used as a molecular reactors, as well [18, 20]. 

Nucleic acids, DNA and RNA, are attractive biopolymers that can be used for biomedical applications [175,176], nanostructure fabrication [177,178], computing [179,180], and materials for electron-conduction [181,182]. Immobilization of DNA and RNA in well-defined nanostructures would be one of the most unique subjects in current nanotechnology. Unfortunately, a silica surface cannot usually adsorb duplex DNA in aqueous solution due to the electrostatic repulsion between the silica surface and polyanionic DNA. However, Fujiwara et al. recently found that duplex DNA in protonated phosphoric acid form can adsorb on mesoporous silicates, even in low-salt aqueous solution [183]. The DNA adsorption behavior depended much on the pore size of the mesoporous silica. Plausible models of DNA accommodation in mesopore silica channels are depicted in Figure 4.20. Inclusion of duplex DNA in mesoporous silicates with larger pores, around 3.8 nm diameter, would be accompanied by the formation of four water monolayers on the silica surface of the mesoporous inner channel (Figure 4.20A), where sufficient quantities of Si—OH groups remained after solvent extraction of the template (not by calcination). 

Accurate control of microstructure on nanometric scale makes it possible to control magnetic and mechanical properties to a hitherto unattainable degree. In particular, magnetic nanostructures have recently become the subject of an increasing number of experimental and theoretical studies. The materials are made of alternating layers, around 10 A thick, of magnetic (e.g., cobalt) and nonmagnetic metals (e.g., copper). 

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