A nonlinear calibration curve for volume fraction vs integrated intensity ratio was obtained the monoclinic-tetragonal ZrO2 system by using X-ray powder pattern-fitting and pattern-decomposition techniques. The empirical equation agrees well with theoretical one. By this equation, deviation from linearity (6.8% maximum) resulting difference of corresponding reflections two phases can be estimated quite accurately.

An equation for a nonlinear calibration curve of volume fraction vs integrated intensity ratio is presented monoclinic‐stabilized cubic ZrO 2 systems containing YO 1.5 , CaO, and MgO. A parameter in the was evaluated theoretically given range solid solution compositions.

A structural phase transition between the cubic (space group, Fm 3 m) and tetragonal P 4 2 /nmc) phases in a zirconia–ceria solid solution (Zr 1−x Ce x O ) has been observed by Raman spectroscopy. The cubic–tetragonal ( c–t″ boundary compositionally homogeneous samples exists at composition X 0 (0.8 < 0.9) room temperature, where t ″ is defined as whose axial ratio c/a equals unity. decreases with an increase of ceria concentration becomes 1 X′ (0.65 0.7) temperature. sample ZrO . By...

Local structures in ceria-based materials were investigated by UV resonance Raman spectroscopy using a 363.8 nm laser line for the first time. In spectra of highly crystalline and undoped ceria, overtone LO series are clearly detected due to multiphonon relaxation effect. Gd3+ doping ceria additionally activates disorder bands that attributable lattice spaces with or without an oxygen vacancy. The crystal size dependency suggests Ce3+ ions preferably form MO8-type (M = Ce3+) complex...

Noble metal (gold or silver) nanoparticles patterned films are typically used as substrates for surface-enhanced Raman spectroscopy (SERS). Two-dimensional (2D) carbides and nitrides (MXenes) exhibit unique electronic optical properties, including metallic conductivity plasmon resonance in the visible near-infrared range, making them promising candidates a wide variety of applications. Herein, we show that 2D titanium carbide, Ti3C2Tx, enhances signal from organic dyes on substrate solution....

A facile urea-assisted hydrothermal synthesis and systematic characterization of hydroxyapatite (HA) with calcium nitrate tetrahydrate diammonium hydrogen phosphate as precursors are reported. The advantage the proposed technique over previously reported synthetic approaches is simple but precise control HA crystals morphology, which achieved by employing an intensive, stepwise, slow thermal decomposition urea well varying initial concentrations starting reagents. Whereas plate-, hexagonal...

Abstract This account focuses on the synthesis and characteristics of ceramics prepared by Pechini-type in-situ polymerizable complex (IPC) method. The current status IPC method is reviewed, principle underlying chemistry illustrated with a special emphasis its intrinsic advantage over other solution-based technologies. has ability to prepare multicomponent oxides good homogeneity through mixing at molecular level. importance “polymerization” itself in route demonstrated comparing...

The formation process of titania based nanorods during hydrothermal synthesis starting from an amorphous TiO2·nH2O gel has been investigated. Sodium tri-titanate (Na2Ti3O7) particles with a rodlike morphology were prepared by simple in the presence concentrated NaOH aqueous solution. ion exchange reaction synthesized Na2Ti3O7 HCl under ultrasonic treatment promotes complete sodium substitution and H2Ti3O7 nanorods. Low-temperature annealing as-produced leads to loss layered crystal structure...

Ultrafine tetragonal ZrO 2 powder was prepared by hydrothermal treatment at 100 MPa of amorphous hydrous zirconia with distilled water and LiCl KBr solutions. The resulting consisted well‐crystallized particles; 200°C, the particle size 16 nm 500°C, 30 nm. Under conditions appears to crystallize topotactically on nuclei in zirconia.

We present a method to fill 2−5-nm-diameter channels of closed multiwalled carbon nanotubes (MWNT) with an aqueous fluid and perform in situ high-resolution observations dynamic behavior this confined system. Transmission electron microscope (TEM) confirm the successful filling two types MWNTs reveal disordered gas/liquid interfaces contrasting smooth curved menisci visualized previously MWNT diameter above 10 nm. Electron energy loss spectroscopy (EELS) dispersive spectrometry (EDS)...

A complex pattern: Single-phase brookite, rutile, and rutile–anatase nanoparticles can be prepared from the new water-soluble titanium(IV) (NH4)6[Ti4(C2H2O3)4(C2H3O3)2(O2)4O2]⋅4 H2O. It appears that structural similarity of anion to brookite architecture allows directional synthesis nanopowders in a pure form (see scheme).

The phase diagram of the system ZrO 2 ‐CeO was rein‐vestigated using hydrothermal techniques. Cubic, tetragonal, and monoclinic solid solutions are present in this system. tetragonal solution decomposes to cubic by a eutectoid reaction at 1050°50°C. solubility limits about 18 70 mol% CeO , respectively, 1400°C, 16 80 1200°C. Solubility 1.5 88 1000°C, 98 800°C, respectively. compound Ce Zr 3 O 10 is not found

In the ZrO 2 -YO 1.5 solid solutions, phase changes among cubic (Fm3m, Z=4), t″ form and t' were investigated by neutron X-ray powder diffraction, where forms are defined as tetragonal phases (P4 /nmc, Z=2) with axial ratios of c/a f =1 >1, respectively, which prepared a diffusionless transition from high-temperature during quenching. is lattice parameter pseudo-fluorite cell