The characterization of mixed oxides of TiO2/SiO2 and TiO2/Al2O3 prepared by sol-gel methods is described. Application of the TiO2/Al2O3 material for the photocatalytic decomposition of salicylic acid gave improved activity relative to TiO2-only materials. The photocatalytic activity of TiO2/SiO2, TiO2/Al2O3, and TiO2 toward the photocatalytic decomposition of phenol demonstrated the enhancemen...

The Fe3O4/CeO2 magnetic photocatalyst was prepared by coating directly onto the surface of magnetic Fe3O4 particles. However a direct contact of CeO2 onto the surface of magnetic Fe3O4 particles presented unfavorable heterojunction, thus the SiO2 barrier layer between magnetic Fe3O4 and CeO2 was prepared as a core-shell stucture to reduce the negative effect by combining three steps of the hydr...

SiO2-TiO2 mixed oxides have been prepared by sol-gel technique from titanium tetraisopropoxide and tetraethylorthosilicate. The prepared materials were characterized by X-ray diffraction, FT-IR spectroscopy, scanning electron microscopy, nitrogen physisorption and UV-vis diffuse reflectance spectroscopy. The results indicate that compared to pure TiO2, the SiO2-TiO2 mixed oxides show higher the...

Ultrafine copper nanoparticles (Cu NPs) within porous silica nanospheres (Cu@SiO2) were prepared via a simple one-pot synthetic route in a reverse micelle system and characterized by SEM, TEM, EDX, XRD, N2 adsorption-desorption, CO-TPD, XPS, and ICP methods. The characterized results show that ultrafine Cu NPs with diameter of around 2 nm are effectively embedded in the center of well-proportio...

During fluorocarbon plasma etching of SiO2 , a polymer passivation layer is generally deposited on the surface of the wafer. The polymer layer regulates the etch by limiting the availability of activation energy and reactants, and providing the fuel for removal of oxygen. To investigate these processes, a surface reaction mechanism for fluorocarbon plasma etching of SiO2 has been developed. The...

In this paper, the Co@SiO2 core-shell nanoparticles were prepared by the sol-gel method. The oxidization of Co core nanoparticles was studied by the synchrotron radiation-based techniques including in situ X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) up to 800°C in air and N2 protection conditions, respectively. It was found that the oxidization of Co cores is undergoing t...

Wettability and interface microstructure were studied for Nb-containing melts in the contact with ceramic oxide materials of Al2O3-SiO2 system. Ni-40.5 at.%Nb and Au-(0-20) at.%Nb alloys were investigated as prospective alloys for high temperature brazes. Ceramic samples ranged in composition from pure Al2O3 to pure SiO2. The wettability was measured by the sessile drop method. Microstructure o...

Cu nano-particles (Cu-NPs) were embedded into the SiO2 layer of a Cu/SiO2/Pt structure to examine their influence on resistive switching characteristics. The device showed a reversible resistive switching behavior, which was due to the formation and rupture of a Cu-conducting filament with an electrochemical reaction. The Cu-NPs enhanced the local electric field within the SiO2 layer, which cau...

The accurate value of thermal expansion coefficient ( ) of thin film is an important thermal property in the design of microelectronic devices and microsystem. This research presents a microbridge buckling deformation caused by the residual stresses to determine the of thermal oxide (SiO2) film. The extraction of is supported through experimental means and finite element analysis (FEM) of the b...