Nanocrystalline materials have recently received significant attention in the area of advanced materials engineering due to their improved physical and mechanical properties. A solid-solution nanocrystalline powder, (Ti,Mo)C, was prepared via high-energy milling of Ti-Mo alloys with graphite. Using XRD data, the synthesis process was investigated in terms of the phase evolution. Rapid sintering of nanostuctured (Ti,Mo)C hard materials was performed using a pulsed current activated sintering process (PCAS). This process allows quick densification to near theoretical density and inhibits grain growth. A dense, nanostructured (Ti,Mo)C hard material with a relative density of up to 96 % was produced by simultaneous application of 80 MPa and a pulsed current for 2 min. The average grain size of the (Ti,Mo)C was lower than 150 nm. The hardness and fracture toughness of the dense (Ti,Mo)C produced by PCAS were also evaluated. The fracture toughness of the (Ti,Mo)C was higher than that of TiC.

The printing of nanomaterials onto certain substrates is one of the key technologies behind high-speed interconnection and high-performance electronic devices. For the printing of next-generation electronic devices, a printing process which can be applied to a flexible substrate is needed. A printing process on a flexible substrate requires a lowtemperature, non-vacuum process due to the physical properties of the substrate. In this study, we obtained well-ordered Ag nanowires using modified gravure printing techniques. Ag nanowires are synthesized by a silver nitrate (AgNO3) reduction process in an ethylene glycol solution. Ag nanowires were well aligned by hydrodynamic force on a micro-engraved Si substrate. With the three-dimensional structure of polydimethylsiloxane (PDMS), which has an inverse morphology relative to the micro-engraved Si substrate, the sub-micron alignment of Ag nanowires is possible. This technique can solve the performance problems associated with conventional organic materials. Also, given that this technique enables large-area printing, it has great applicability not only as a next-generation printing technology but also in a range of other fields.

To investigate the effects of co-solvents on the morphology of nano-scale zein materials, zein solutions were electrospun with different co-solvent ratios of EtOH/H2O. Different zein solution concentrations were used to study the effects of the zein content on the electrospun materials. The resulting electrospun materials were all characterized using field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The diameters of the electrospun nanoparticles and nanofibers were found to increase when increasing the EtOH ratio at certain zein concentrations. Furthermore, increasing the zein content changed the morphology of the electrospun materials from nanoparticles to nanofibers.

Carbon nanomaterials in organic photovoltaic (OPV) cells have attracted a great deal of interest for the development of high-efficiency, flexible, and low-cost solar cells. Due to the complicated structure of OPV devices, the electrical properties and dispersion behavior of the carbon nanomaterials should be controlled carefully in order for them to be used as materials in OPV devices. In this paper, a fundamental theory of the electrical properties and dispersion behavior of carbon nanomaterials is reviewed. Based on this review, a state-of-the-art OPV device composed of carbon nanomaterials, along with issues related to such devices, are discussed.

Multilayer ceramic capacitor (MLCC) miniaturization has increased the demand for superfine powder due to its thin dielectric layer. Hydrothermally synthesized powder a pseudo-cubic phase resulting in poor dielectric properties due to size effect and hydroxyl ion inclusion in the lattice. We attempted a superfine (lower than 100 nm) highly tetragonal powder via a solvothermal method without precipitating agent. The lattice parameters and the relative amounts of tetragonal and cubic phases were determined using Rietveld refinement.

The work reported in this paper relates to preparation and characterization of carbon nanomaterials by CVD method on different substrates by decomposition of certain hydrocarbons at 550-800℃ using a horizontal quartz tube reactor. Monometallic and bimetallic catalyst system of iron and nickel were used for the preparation of different carbon nanomaterials. The influence of various parameters such as substrate/catalyst preparation parameters, the nature of substrate, catalyst concentration, reaction time and temperature on the growth, yield and alignment of carbon nanotubes has been studied. The characterization of carbon nanomaterials has been carried out using SEM, TEM and TGA. The carbon nanomaterials developed were vertically aligned on a large area of flat quartz substrate.

This study evaluated the photocatalytic oxidation efficiency of volatile organic compounds by Cu2O -TiO2 under visible-light irradiation. Cu2O-TiO2 was synthesized by an ultrasonic-assisted method. The XRD result indicated successful p-n type photocatalysts. However, no diffraction peaks belonging to TiO2 were observed for the Cu2O-TiO2. The Uv-vis spectra result revealed that the synthesized Cu2O-TiO2 can be activated under visible-light irradiation. The FE-TEM/EDS result showed the formation of synthesized nanocomposites in the commercial P25 TiO2, the undoped TiO2, and Cu2O-TiO2 and componential analysis in the undoped TiO2 and Cu2O-TiO2. The photocatalytic oxidation efficiencies of benzene, toluene, ethylbenzene, and o-xylene with Cu2O-TiO2 were higher than those of P25 TiO2 and undoped TiO2. These results indicate that the prepared Cu2O-TiO2 photocatalyst can be applied effectively to control gaseous BTEX.

In this study, we evaluated the photocatalytic oxidation efficiency of aromatic volatile hydrocarbons by using WO3–doped TiO2 nanotubes (WTNTs) under visible-light irradiation. One-dimensional WTNTs were synthesized by ultrasonic-assisted hydrothermal method and impregnation. XRD analysis revealed successful incorporation of WO3 into TiO2 nanotube (TNT) structures. UV-Vis spectra exhibited that the synthesized WTNT samples can be activated under visible light irradiation. FE-SEM and TEM images showed the one-dimensional structure of the prepared TNTs and WTNTs. The photocatalytic oxidation efficiencies of toluene, ethylbenzene, and o-xylene were higher using WTNT samples than undoped TNT. These results were explained based on the charge separation ability, adsorption capability, and light absorption of the sample photocatalysts. Among the different light sources, light-emitting-diodes (LEDs) are more highly energy-efficient than 8-W daylight used for the photocatalytic oxidation of toluene, ethylbenzene, and o-xylene, though the photocatalytic oxidation efficiency is higher for 8-W daylight.

Engineered nanomaterials (ENMs) can be released to humans and the environment through the generation of waste containing engineered nanomaterials (WCNMs) and the use and disposal of nano-products. Nanoparticles can also be introduced intentionally or unintentionally into waste streams. This study examined WCNMs in domestic industries, and target nanomaterials, such as silicon dioxide, titanium oxide, zinc oxide, nano silver, and carbon nanotubes (CNTs), were selected. We tested 48 samples, such as dust, sludge, ash, and by-products from manufacturing facilities and waste treatment facilities. We analyzed leaching and content concentrations for heavy metals and hazardous constituents of the waste. Chemical compositions were also measured by XRD and XRF, and the unique properties of nano-waste were identified by using a particle size distribution analyzer and TEM. The dust and sludge generated from manufacturing facilities and the use of nanomaterials showed higher concentrations of metals such as lead, arsenic, chromium, barium, and zinc. Oiled cloths from facilities using nano silver revealed high concentrations of copper, and the leaching concentrations of copper and lead in fly ash were higher than those in bottom ash. In XRF measurements at the facilities, we detected compounds such as silicon dioxide, sulfur trioxide, calcium oxide, titanium dioxide, and zinc oxide. We found several chemicals such as calcium oxide and silicon dioxide in the bottom ash of waste incinerators.

In this study, we investigated the distribution of domestic nanomaterials. Zinc oxide (ZnO), titanium dioxide (TiO2), and silver (Ag) nanoparticles, as well as carbon (C) nanotubes, were selected, and their circulation and quantity in use was investigated. We also analyzed leaching and of heavy metals in nanowaste. Chemical composition was determined using Xray diffraction and fluorescence (XRD and XRF) and transmission electron microscopy (TEM). Using XRF and XRD analysis, sludge from a facility using zinc oxide was found to have silicon dioxide (SiO2) and TiO2 as its main components. Sludge from a facility using TiO2 was found to have TiO2 as its main component. Samples of Ag nanoparticle and C nanotubes manufacturer measured elemental components of Ag and C, respectively. TEM analysis showed Si O2 in the form of dust sample from a facility manufacturing ZnO. Carbon nanotube samples of manufacturers were in the form of fibers. Leaching test results showed low concentrations compared to the regulation criteria of the Wastes Control Act. Content result of Zn was detected at -111.7 ~ 24,843.4 mg/kg in ZnO samples. Content result of Ti was detected at 1.51 ~ 35.28 mg/kg in TiO2 samples. Oil mop samples of Ag nanoparticle were detected in Ag (29,643.07 mg/kg) and Cu (15,600.8 mg/kg).