The research and development of the low-temperature combustion synthesis (LCS) of the ultrafine advanced ceramics and nanomaterials are summarized in this paper. The principle and method of LCS and its application are briefly reviewed. Recent innovations in the combustion and processing parameters have resulted in a better understanding of combustion phenomena and control of microstructure and property of the products.

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High purity silicon carbide ceramics are requested for semiconductor industries. Although the carbothermic reduction process of silica by carbon has been widely used to produce silicon carbide ceramics at present, some additional treatments to remove unreacted silica and carbon are usually required in this process. On the other hand, precursor processing is attractive for synthesizing pure ceramic materials by using liquid compounds containing much less metallic impurities. In this study, chemical processing of preceramic precursors was investigated in order to synthesize silicon carbide powders, in view of process efficiency and powder properties.

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Precursors for silicon carbide powders were prepared from liquid mixtures of nano-micro carbon particles (carbon blacks, charcoal or powder diamond), phenolic resin and ethyl silicate. After the geletion, drying and pyrolysis at 1273K, carbon-silica hybrids were obtained with C/SiO2 ratios of ca. 3. In these materials, a part of carbon existed as nano-micro carbon particles dispersed in matrix. The other carbon, originated from phenolic resin, was located in the surrounding matrix area. These carbon-silica hybrids were heat-treated at 1838K in an Ar gas flow to obtain SiC powders with carbothermic reduction process. Conversion process of the hybrids to SiC was monitored by thermo gravimetric analysis. Influence of the state of the embedded carbon particles on conversion rates and resulting SiC particle morphology were investigated.

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The surfactant and acid treatment have been used to modify the CNTs surface and then incorporated the functionalized CNTs into various ceramic matrices. The preparation of ceramic nanoparticle-immobilized CNTs not only improves the homogeneous distribution of CNTs in the ceramic matrices, but also makes the combination between two phases more tight. Various measurements including mechanical, electrical, and electrochemical properties clearly reveal that the preparation of true CNT-based composite materials possess obvious enhanced properties. The preparation of carbon nanotube-incorporated structural and functional ceramics is very promising for the development of new-style ceramic composite, electric devices, electrochemical capacitors, and so on.

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The aim of our study is to obtain BN nanofibers from borazine oligomer; which gives a high ceramic yield in the absence of the carbon. The commercially available anodic Al membrane was used as a template. The fibers were characterized by FT-IR, XRD, and SEM. It was found that the BN nanofibers of 20-100nm in diameter were formed by treating borazine oligomer with Al templates.

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Alumina was joined via In/Ag alloy/In interlayers at 973 and 1073 K for 5.4 to 86.4 ks at 5 MPa by hot pressing. The specimen joined at 973 K for 86.4 ks had higher 4-point bending strength than that joined at 1073 K for 86.4 ks. Titanium in Ag alloy diffused to the Ag alloy/alumina interface after joining at 1073 K for 86.4 ks. TEM observation of the specimen joined at 1073 K for 86.4 ks revealed that thin layer formed at the Ag alloy/alumina interface, and nano pores formed between the thin layer and alumina.

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La<0.7/SUB>Ca<0.3/SUB>MnO<3/SUB> (LCMO) thin films exhibit a metal-insulator transition at the Curie temperature which is accompanied by a large temperature coefficient of resistance (TCR) in the region of the phase transition. Therefore, these materials can be ideal candidates for IR detectors utilizing resistance bolometer. In this study, epitaxial LCMO thin films were successfully prepared on LSAT ([LaAlO<3/SUB>-SrAlTaO<3/SUB>]-[(LaAlO<3/SUB>)<0.3/SUB>-(SrAlTaO<6/SUB>)<0.7/SUB>]) single-crystal substrates by a new excimer-laser metal-organic deposition (ELMOD) process. A KrF excimer laser irradiation at a substrate temperature of 500 C and a fluence of 80 mJ/cm<2/SUP> is sufficient to obtain high epitaxial films with different thicknesses (20-100 nm). Compared to the films prepared on SrTiO<3/SUB> substrates, the LCMO prepared on LSAT exhibit the highest values of TCR, which can reach 7.5% at 210 K.

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Functional non-oxide ceramic materials have gained a great interest for potential applications in opto-electronic device industries. In particular, the wide band-gap semiconductor GaN and new superconducting MgB2 ceramics have been intensively studied in micro/nanometer scaled electronics. However, their thermodynamic nature of low-temperature decomposition makes it difficult to densify highly using a conventional sintering technique, which limits the application of these materials to various deposition processes which need the highly-densified bulk target. We have succeeded in densifying GaN and MgB2 up to 98% RD without any additive using a pulsed electric current-activated sintering technique and investigated the microstructural features of the sintered bodies using a variety of microscopic tools including SEM and TEM. In addition, amorphous GaN nanoparticles/film and superconducting MgB2 thin film have been successfully prepared using a pulsed-laser ablation of these sintered pellets, resulting in the quantum confinement effect in the small sized GaN (~5nm), blue luminescence (~2.8eV) from amorphous GaN film and high Tc MgB2 thin film comparable to that of MgB2 bulk. These results suggest that our approach be greatly effective for micro/nano scaled fabrication of these materials, leading to the high efficiency of the electronic device process.

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In this work, we design the buffer solution structures by addingmonodispersed ceramic nanoparticles to the buffer solution. This workfocuses the effect of the buffer solution structures on DNA analysis bymicro-capillary electrophoresis, which will realize high-mobilityand high-resolution of double-strand deoxyribonucleic acid (dsDNA) analysis.Various particle sizes of monodispersed SiO2 and other nanohybridnanoparticles were mixed with conventional 0.7% hydroxyl propyl methylcellulose (HPMC) buffer solution to design the buffer solution structures.These buffuer solution design achieved perfect separation of the DNAspecimen (100 bp to 1.5 kbp) if buffer solution designs were optimized. Wealso discuss the mechanism of the improvement for DNA analysis by usingceramic nanoparticles during electrophoresis.

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Materials with large third-order optical nonlinearity and ultra-fast response time are important for future applications in a number of fields, such as optical telecommunications, data storage, optical computation and information processing. Nano-sized gold and silver composite materials have attracted much attention because of their high nonlinear susceptibilities due to local field enhancement near the surface plasmon resonance (SPR). However, these high susceptibilities are only observed at the SPR wavelength (around 530 and 400 nm for Au and Ag, respectively), and decrease dramatically at wavelengths far from the SPR position, which limits the practical applications of these materials. Simple materials exhibiting high nonlinearity and fast response speed at multiple frequencies, if developed, would be ideal for novel multi-mode optical devices. Here, we demonstrate a simple strategy for self-assembling amorphous SiO2-coated linear-chains of gold nanoparticles (so-called nanochains) on glass substrates for multi-mode nonlinear optical switches.

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We have developing facile preparation method of size and shape controlled metal nanoparticles in a liquid phase by the reduction of metal ion in the presence of organic protective agent. Such metal nanoparticles are applied as active agents of supported catalysts for the preparation of carbon nanotube etc.

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Powder compact of Al4SiC4 with SiC and/or C was sintered, and the oxidation and electric property of the sintered body were examined. Oxide protective layer formed near the surface inhibits oxidation of the body. It became clear to become a heating element by turning on electricity.

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We have been studied the fabrication of the metal oxide thin films using solution process through the hydrolysis of metal-fluoro complex, the Liquid Phase Deposition (LPD) methods. We have obtained more than 30 kinds of metal oxide species as the thin films which has a dense and strong adhesion with simple equipment and any type of substrates. Due to such properties, the metal oxide is deposited on the porous, complex, and high-dimensional surface, such as micro-fabricated substrate, opal-structured polymer, and micelle structure. We report that the nano- and microscale structure of the deposited films, and the deposition process of the high dimensional structure.

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Both high efficiency and low cost is important to realize a practical process for the solar cell generation. TiO₂ electrode film with controlled morphology and crystalline on flexible substrates of large areas may be one of resolutions for this problem. Here we present an aqueous-solution-based process for the evolution of morphology and crystalline of TiO₂ films on a polymer substrate. The films demonstrated anatase, rutile or amorphous state under different treatment conditions in terms of pH, temperature and/or additives. Solar cells using the prepared TiO₂ will also be characterized and the result will be presented.

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