Papers by Keyword: Indium Oxide

Abstract: In this paper, mesoporous indium oxide has been synthesized by the hard template route from the SBA-15 silica template. The results characterized from XRD, and N₂ adsorption-desorption demonstrated that the synthesis can be controlled successfully in nanometer (meso-structure) scale. The obtained sample was investigated as humidity sensing material by coating on a ceramic plate, and the humidity sensing performance can be enhanced up to more than three orders of magnitude without any doping. Further testing proved that it is a promising humidity sensing material and can be widely used, and a possible mechanism was also provided.

Abstract: Ultra-thin fibers of indium oxide (In₂O₃) were prepared by sol-gel processing and the electrospinning technique using polyvinylpyrrolidone (PVP) and indium nitrate as precursors. The fibers were characterized by the thermogravimetric analysis, scanning electron microscopy, X-ray diffraction and room temperature photoluminescence spectra. It was observed that the In₂O₃ nanofibers exhibited photoluminescence peaks centered at 526 and 590 nm, corresponding to the defeat-related deep-level emission.

Abstract: In this chapter Perturbed Angular Correlation (PAC) experiments on binary oxides are described. These experiments provide local-scale fingerprints about the formation, identification, and lattice environment of defect complexes at the PAC probe site. The potential of the PAC observations in conjunction with ab initio calculations is shown. Measurements of the electric-field gradient at impurity sites using ¹¹¹Cd and ¹⁸¹Ta probes are reviewed. Special attention is paid to oxides with the bixbyite structure. The case of In₂O₃ is particularly analyzed. Results obtained with HfO₂, in form of coarse grain or nano particles, are described. The potential results that can be obtained from Density Functional Theory ab initio calculations in doped systems are shown describing the main results observed in many impurity-host systems.

Abstract: In this study, the micro gas sensor for NOx gas was fabricated by using a MEMS technology and sol-gel process. The sensing electrode and micro heater were designed to be a co-planar typed structure in the Pt thin film layer. The fabricated micro platform had a low power consumption of 67 mW at 2.0 V of heater voltage and 300°C of operating temperature. Indium oxide as a sensing material for NOx gas was synthesized by a sol-gel process with indium isopropoxide. The particle size of synthesized In2O3 was identified as about 50 nm. The maximum gas sensitivity as relative resistance (Rs = Rgas / Rair) occurred at 300°C with the value of 8.0 at 1 ppm NO2 gas. The present study shows that a MEMS-based gas sensor is a potential candidate for the automobile AQS (air quality system) gas sensor with many advantages of small dimension, high sensitivity, short response time and low power consumption.

Abstract: Indium oxide (In2O3) films were successfully grown on LiAlO2 substrates using the triethylindium (TEI) as a precursor in the presence of oxygen in the metalorganic chemical vapor deposition process. We have established the correlation between the substrate temperature and the structural properties. The grain structures were clearly shown on the surface of the films deposited at 350°C. The root mean square (RMS) surface roughness of the In2O3 films increased with increasing the substrate temperature. A photoluminescence measurement at room temperature exhibited a yellow-green emission band centered at 585 nm.

Abstract: This paper reports the fabrication of indium oxide (In2O3) films using a triethylindium and oxygen mixture. The deposition has been carried out on TiAlN substrates (200-350°C). We have established the correlation between the substrate temperature and the structural properties. The films deposited at 300-350°C were polycrystalline, whereas those deposited at 200°C was close to amorphous. XRD analysis and SEM images indicated that the films grown at 350°C had grained structures with the (222) preferred orientation. The room-temperature photoluminescence spectra of the In2O3 films exhibited a visible light emission.

Abstract: Indium oxide (In2O3) films was deposited on TiN substrates by the metal organic chemical vapor deposition technique using a triethylindium and oxygen mixture. The films deposited at 250-350°C were polycrystalline, while that deposited at 200°C was close to amorphous. XRD and SEM analyses indicated that the films grown at 350°C had grained structures with the (222) preferred orientation.

Abstract: Monodispersive and uniform particles have many potential applications. The objectives of this study are trying to synthesize and control the morphology of monodispersive indium oxide (In2O3)particles through hydrothermal process with the help of PVP (polyvinylpyrrolidone) and urea additions. Various cubic, ellipse, or shuttle-like In2O3 particles were synthesized by using hydrothermal conditions (65-85oC). The effects of Sr nitrate were studied. Spherical particles could not be synthesized. The aspect ratio of the In2O3 particle reduced as the concentration of Sr nitrate increased. Crystalline In2O3 phase appeared above 300oC.

Abstract: Indium oxide, a wide band gap transparent conductor, is of great interest for many device applications due to its unusual combination of high transparency in the visible region and high electrical conductivity. Several methods, comprising all three phases, namely, the solid phase, the solution phase, as well as the vapor phase, have been used for the preparation of In2O3 powders and thin films. In this work, indium oxide nanoparticles were synthesized by homogeneous precipitation using hexamethylenetetramine as ligand and indium nitrate or indium chloride as precursor materials. Thermogravimetry and differential thermal analysis results evidenced the relatively low temperature for crystallization of indium oxide. Spherical clusters consisting of about 8 nm of diameter indium oxide nanoparticles were obtained after thermal decomposition at 400 °C for 2 h, as revealed by X-ray diffraction experiments and nitrogen adsorption measurements. Transmission electron microscopy observations confirm the single-crystalline nature of the prepared nanoparticles. This material exhibits photoluminescence emission at room temperature with peak onset at 315 nm as a consequence of the small size of the particles.

Abstract: In2O3 materials consisting of dense arrays of vertically aligned rod-like structures were deposited on sapphire substrates by thermal chemical vapor deposition (CVD) using triethylindium (TEI) and oxygen as precursors at a substrate temperature of 350 oC. The rod-like structure with a triangular cross section had a cubic structure, exhibiting preferred crystallographic orientation in the [111] direction. The photoluminescence spectra of In2O3 structures under excitation at 325 nm revealed a visible emission.