A new method has been used to produce uniaxially aligned small single crystals of ${\mathrm{Y}}_{1}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$. The superconducting critical current deduced from magnetization data is strongly field dependent and highly anisotropic. In the basal plane at $T=4.2$ K we estimate that zero in excess ${10}^{7}$ A/${\mathrm{cm}}^{2}$.

Siloxane-anchored, self-assembled monolayers (SAMs) on single crystal Si were prepared with a variety of surface functional groups using commercially available surfactant (1-bromo-11-(trichlorosilyl)undecane) followed by in situ transformations. Polar (thioacetate and thiol), nonpolar (methyl), acidic (sulfonic carboxylic), basic (various amines), ionic (alkylammonium) functionalities prepared. For primary amine sulfonate surfaces, the degree charge as function pH was determined ex X-ray...

Undoped or Y 2 O 3 ‐doped ZrO thin films were deposited on self‐assembled monolayers (SAMs) with either sulfonate methyl terminal functionalities single‐crystal silicon substrates. The undoped formed by enhanced hydrolysis of zirconium sulfate (Zr(SO 4 )·4H O) solutions in the presence HCl at 70°C. Typically, these a mixture two phases: nanocrystalline tetragonal‐ ( t ‐) and an amorphous basic sulfate. However, little no material could be produced. mechanism film formation growth kinetics...

Liquid-phase deposition (LPD) from aqueous solution, under mild conditions of temperature (≤55 °C) and pH (2.88−3.88), can produce thin (0.1−1.0 μm), adherent titania (TiO2) films. This paper reports a systematic study LPD TiO2 films on variously prepared silicon wafer substrates, including (to our knowledge for the first time with LPD) several types sulfonated surfaces (including self-assembled monolayers polyelectrolyte multilayers). The growth rate crystallinity these could be controlled...

Patterned thin films of TiO2 were deposited from aqueous solution onto photopatterned self-assembled monolayer (SAM) on Si substrates. Regions the SAM containing sulfonate surface functionality created by photo-oxidation initially thioacetate groups through a mask. The nanocrystalline TiO2-on-SAM selectively photolyzed regions SAM. electrical properties such assessed for potential microelectronic device applications. Current–voltage and capacitance–voltage measurements made nonpatterned...

The room-temperature cation distributions in bulk CoFe2O4 samples, cooled at rates between <10−2 and ∼103 °C s−1, have been determined using Mössbauer spectroscopy an 80-kOe magnetic field. With increasing cooling rate, the quenched structure departs increasingly from mostly ordered distribution ordinarily observed room temperature. However, disorder appears to saturate just short of a random very high rates. These results are interpreted terms simple relaxation model redistribution...

TiO 2 thin films were synthesized onto sulfonated self-assembled organic monolayers from Ti4+ aqueous solutions at low temperature (80 °C). The deposited TiO2 characterized using Rutherford backscattering spectroscopy and transmission electron microscopy. electrical properties of the measured capacitance–voltage (C–V) current–voltage techniques. From C–V measurements, dielectric constants calculated to be in range 24–57 for as-deposited 67–97 annealed 400 °C. For samples, breakdown voltage...

The synthesis, by two different reaction pathways, of boron-modified polysilylcarbodi-imides general type {B[C2H4Si(R)NCN]3}n (R =­singly bonded organic ligand) and the plastic-forming thermal behavior these polymers are described. Compounds [2a, R = H; 2b, CH3; 2c, (NCN)0.5] can be obtained treatment vinyl-substituted [(H2CCH)(R)SiNCN]n [1a, 1b, 1c, with borane dimethylsulfide BH3·S(CH3)2. 1a–1c themselves accessible via chlorosilanes (H2C=CH)-­(R)SiCl2 cyanamide H2N-C≡N in presence...

We proposed a novel method to fabricate nano/micro-scaled patterns of thin films and successfully fabricated anatase TiO2 in an aqueous solution at 50 8C. The patterned self-assembled monolayer (SAM) having octadecyltrichlorosilane (OTS) regions silanol was immersed containing Ti precursor subjected ultrasonication for several hours. difference adhesion on substrates employed the site-selective elimination method. Heterogeneously nucleated homogeneously particles adhering OTS–SAM could be...

Thin Y-containing films have been deposited at 80 °C from aqueous solutions of YNO3⋅5H2O and urea on bare single crystal Si wafers, wafers coated with sulfonate-functionalized organic self-assembled monolayers. The as-deposited are believed to be an amorphous yttrium basic carbonate can completely transformed 600 in air crystalline Y2O3. Capacitance–voltage measurements these showed good dielectric properties, a relative permitivity 18, more than factor four higher that SiO2.

Mesoporous solid solutions of anatase-based titanium−vanadium oxides were synthesized from aqueous solutions. The V/Ti ratio was determined by the composition deposition solution, while morphology and nanoscale porosity controlled using micelles surfactants cetyltrimethylammonium bromide (CTAB), or hexadecylamine (HDA). use CTAB resulted in mesoporous powders, whereas HDA yielded clusters nanotubes. As compared to materials same made without a surfactant, catalyst with had 50% higher...

Bi 1.5 SrCaCu 2 O z was prepared in the glassy state by rapid quenching of melt. The recrystallization glass during various heat treatments studied differential thermal analysis, X‐ray diffraction, scanning electron microscopy, and resistivity measurements. Activation energies frequency factors for crystallization events below 600°C were determined nonisothermal calorimetry. Heating at 450°C formed mainly 2+ x Sr 2− ‐CuO solid solution (“R”). Between 765° 845°C, R reacted slowly with to form...

We have tested the granular magnetization model of Finnemore et al. on a well-characterized sample ${\mathrm{Y}}_{1}$${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{\mathrm{x}}$. The temperature dependence magnetic susceptibility is in excellent agreement with model. In addition, grain size deduced from data (1--2 \ensuremath{\mu}m) reasonable direct scanning-electron-microscopy measurements microstructure.

This review surveys recent advances in the synthesis of oxide materials, primarily as supported thin films but also other forms such free-standing films, mesoporous solids, and nanostructured fibers, from liquid (primarily aqueous) solutions. New studies using chemical bath deposition (CBD), phase (LPD), successive ion layer adsorption reaction (SILAR) to produce single- multi-component role that functionalized substrates can play these techniques, are surveyed. highlights significant new...

Lanthanum strontium manganite (LSM) is widely used in cathodes of solid oxide fuel cells (SOFCs) because its long-term stability and performance at higher operating temperatures (850–900°C). The conductivity LSM depends on the Mn valence, which turn level doping, ratio (La+Sr) to Mn, environment cell (temperature atmosphere). Consequently, determining valences a key issue understanding relationship between conditions. Although defect chemistry has been investigated extensively, this study...