Pore-size expansion of hexagonal-structured nanocrystalline titania/CTAB Nanoskeleton using cosolvent organic molecules

Pore-size expansion of hexagonal-structured assembly of nanocrystalline titania (anatase) combined with cetyltrimethyammonium bromide (CH(3)(CH(2))(15)N(+)(CH(3))(3)Br(-), CTAB) (named as Hex-ncTiO(2)/CTAB Nanoskeleton) was achieved with the aid of cosolvent organic molecules (COMs). The pore-size expanded Hex-ncTiO(2)/CTAB Nanoskeleton was prepared through the sot-gel reaction of titanium oxysulfate sulfuric acid hydrate (TiOSO(4)center dot xH(2)SO(4)center dot xH(2)O, TiOSAH) in an aqueous solution initiated by CAB swollen micelles pre-prepared with the addition of COMs into aqueous CTAB micellar solutions at 60 degrees C (the product was named as Hex-ncTiO(2)/CTAB/COM Nanoskeleton). Long-chain alcohol (1-hexadecanol. C16OH), normal alkane (n-decane, C10) and benzene derivatives (benzene. Bz; 1,3,5-trimethylbenzene, TMB; 1,3,5-triethylbenzene, TEB; 1,3,5-triisopropylbenzene, TiPB) were used as COMs to evaluate the effects of COM solubilization site in CTAB micelles and COM molecular size on the pore-size expansion of the Hex-ncTiO(2)/CTAB/COM Nanoskeleton. We found that 1,3,5-trimethylbenzene (TMB) and 1,3,5-triethylbenzene (TEB) act as effective COMs for pore-size expansion of the Hex-ncTiO(2)/CTAB/COM Nanoskeleton in aqueous media. Pore sizes (average diameters) of the Hex-ncTiO(2)/CTAB/TMB Nanoskeleton and Hex-ncTiO(2)/CTAB/TEB Nanoskeleton were enlarged up to 4.2 nm and 4.3 nm, respectively, while pore size (average diameter) of the Hex-ncTiO(2)/CTAB Nanoskeleton prepared in the absence of any COMs was 2.9 nm. We also revealed that thermal stability of the Hex-ncTiO(2)/CTAB/TMB Nanoskeleton became higher than that of Hex-ncTiO(2)/CTAB Nanoskeleton. The hexagonally pore-structure of the Hex-ncTiO(2)/CTAB/TMB Nanoskeleton was retained up to 400 degrees C, while the hexagonally pore-structure of the Hex-ncTiO(2)/CTAB Nanoskeleton was kept up to 300 degrees C.ArticleCOLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS. 371(1-3):29-39 (2010)journal articl

Electrostatic Levitation Furnace for the ISS

JAXA (Japan Aerospace Exploration Agency) has just started the development of Electrostatic Levitation Furnace to be launched in 2014 for the ISS. This furnace can control the sample position with electrostatic force and heat it above 2000 degree Celsius using semiconductor laser from four different directions. The announcement of Opportunity will be issued soon for this furnace. In this paper, we will show the specifications of this furnace and also the development schedul

In0.3Ga0.7As Plate Crystals Grown by the Traveling Liquidus-Zone (TLZ) Method

The TLZ method is a new crystal growth method which we have invented for the growth of homogeneous mixed crystals. The influence of convection in a melt on the compositional homogeneity of TLZ-grown InxGa1−xAs crystals was investigated by the growth of various diameter crystals on the ground. The results have shown that excellent compositional homogeneity is realized even on the ground if the crystal diameter is less than 2 mm and convection in a melt is suppressed. However, such small diameter crystals cannot be used for device application. Then, we tried plate crystal growth for obtaining large surface area since the limitation of the thickness of plate crystal is useful for suppressing convection in a melt. In0.3Ga0.7As plate crystals with 10 mm width and 2 mm thickness showed good compositional homogeneity as expected but the grown crystals were poly crystals. Single crystallization of plate crystals is required for device fabrication and we made effort for growing plate-like In0.3Ga0.7As single crystals. Here, we report those results obtained in our study in the fiscal year of 2003