Nano-sized Indium Tin Oxide Research Articles

Paraseptal Emphysema in Indium Lung: Tracing the Pathological Footprints of Chronic Exposure.

Indium lung is an occupational lung disease caused by exposure to indium-tin-oxide (ITO) dust. Compared to other occupational lung diseases, indium lung has a shorter latency period and the respiratory status continues to worsen even after exposure to the work environment improves. Paraseptal emphysema which affects mainly the subpleural area is seen on chest images obtained via computed tomography (CT), regardless of the smoking history. However, the pathogenesis of emphysema in indium lung is still unclear. Therefore, we re-evaluated the pathology of three previously reported cases of indium lung. Paraseptal emphysema was observed in both smokers and nonsmokers. Obstructive respiratory impairment worsened over time in the cases with paraseptal emphysema. Many alveolar walls were destroyed independent of the presence or absence of emphysetamous changes or fibrosis. Moreover, bronchiolitis was found to be less common in indium lung than in asbestosis (the most common occupational lung disease) or common cases of chronic obstructive pulmonary disease caused by smoking. It has been shown that ITO causes protease anti-protease imbalance, oxidant-antioxidant imbalance, and continuous, abnormal inflammation (the three major causes of emphysema). In addition, nano-sized ITO is less likely to be trapped in the upper airways and may easily reach the subpleural alveoli. Furthermore, ITO may continue to cause sustained tissue injury at the alveolar level potentially resulting in emphysema. Further studies are needed to elucidate the detailed pathogenesis of indium lung by comparing it with other occupational lung diseases.

Preparation of Nano Sized Indium Tin Oxide (ITO) Powder with Average Particle Size Below 30 nm from Waste ITO Target by Spray Pyrolysis Process

Preparation of Nano Sized Indium Tin Oxide (ITO) Powder with Average Particle Size Below 30 nm from Waste ITO Target by Spray Pyrolysis Process

Effect of Temperature on Nucleation of Nanocrystalline Indium Tin Oxide Synthesized by Electron-Beam Evaporation

Indium tin oxide (ITO) has been widely applied as a transparent conductive layer and optical window in light-emitting diodes, solar cells, and touch screens. In this paper, crystalline nano-sized ITO dendrites are obtained using an electron-beam evaporation technique. The surface morphology of the obtained ITO was studied for substrate temperatures of 25°C, 130°C, 180°C, and 300°C. Nano-sized crystalline dendrites were synthesized only at a substrate temperature of 300°C. The dendrites had a cubic structure, confirmed by the results of x-ray diffraction and transmission electron microscopy. The growth mechanism of the nano-crystalline dendrites could be explained by a vapor–liquid–solid (VLS) growth model. The catalysts of the VLS process were indium and tin droplets, confirmed by varying the substrate temperature, which further influenced the nucleation of the ITO dendrites.

ITO/MWCNT Nanocomposites as New Novel Anode Electrodes for Li-Ion Batteries

In this study, we present a new anode electrode consisting of Indium Tin Oxide and multiwall carbon nanotube based buckypapers for high efficient lithium ion batteries. Core/shell Indium Tin Oxide/Buckypapers were produced by vacuum filtration techniques followed by an rf magnetron sputtering. The nanosized indium tin oxide particles were uniformly anchored onto the surfaces of buckypapers with a mean grain sizes of 2-7 nm confirmed by the FESEM, TEM and XRD results. The as-prepared nanocomposite anode electrodes exhibited outstanding reversible capacity (859, 875 and 895 mA h g(-1) after 50 cycles) and no significant capacity fading is observed after 50 cycles. The unique nanocomposite architecture which integrates both electronic conductivity and buffering matrix design strategies, contributing to enhanced lithium storage performance.

Electrical properties of nano-sized indium tin oxide (ITO) doped with CuO, Cr2O3 and ZrO2

Undoped and doped indium tin oxide (ITO) with different concentrations (2, 4, and 6 mol%) of different dopants (CuO, Cr2O3, and ZrO2) were prepared in the nano-size scale (19–33 nm) using Pechini method. The thermal decomposition of the precursors was studied. The electrical properties of all the prepared samples were investigated. All the investigated systems have higher conductivity than that of ITO. For ITO doped with CuO, as the concentration of CuO increases, the conductivity increases. The highest conductivity was obtained for ITO doped with 6 mol% of CuO. For ITO doped with Cr2O3, as the concentration of Cr2O3 increases the conductivity increases and above 4 mol% Cr2O3 the conductivity decreases. For ITO doped with ZrO2, as the ZrO2 concentration increases, the conductivity increases up to 4 mol% of ZrO2 and then decreases. The band gap was detected for all the investigated systems.

Low temperature preparation of ITO thin films by the coating solutions containing solvothermally synthesized ITO nanoparticles

Indium tin oxide (ITO) thin films were fabricated by spin-coating the coating solutions containing solvothermally synthesized ITO nanoparticles on glass substrates with subsequent low temperature curing. Characterizations of the solvothermally synthesized nanoparticles confirmed that crystalline nano-sized ITO nanoparticles with crystal grain size between 17 and 20nm were successfully obtained by solvothermal treatment of the precursor coprecipitates. By dispersing the solvothermally synthesized ITO nanoparticles in methanol, coating solutions containing well dispersed ITO nanoparticles for subsequent ITO thin film coating were prepared. It was demonstrated that the thin films fabricated by spin-coating the ITO nanoparticle coating solutions on glass substrates followed by 413.15K heat curing under nitrogen atmosphere for 30min were transparent conductive ITO thin films with a sheet resistance of 1.9×105Ω/□.

The Effects of Reaction Factors on the Fabrication of Nano-Sized Indium Tin Oxide Powder by Spray Pyrolysis Process

In this study, waste ITO target is dissolved into hydrochloric acid to generate a complex acid solution. Nano-sized ITO powder with the average particle size below 50 nm is generated from this complex solution by spray pyrolysis process. This study also examines the influences of reaction parameters such as nozzle tip size and air pressure on the properties of the generated ITO powder. When the nozzle tip size is at 1 mm, the particle size distribution becomes more uniform in contrast to the case of other tip sizes, and the average particle size is around 50 nm. When the nozzle tip size increases up to 5 mm, the average particle size increases slightly, yet the particle size distribution becomes extremely irregular. Along with the change of nozzle tip size, the changing tendencies of XRD peak intensity and specific surface area are almost consistent with that of average particle size. Along with the increase of air pressure, the average particle size of the ITO powder gradually decreases, and the particle size distribution becomes more uniform. When the air pressure is at 0.1 kg/cm2, the particle size distribution appears extremely irregular, yet the average particle size is around 70 nm. When the air pressure is at 3 kg/cm2, the average particle size decreases down to 40 nm. Along with the increase of air pressure, the XRD peak intensity gradually decreases and the specific surface area increases.

Indium Tin Oxide (ITO) Coatings Fabricated using Nanoparticle Slurry and Sol

Indium tin oxide (ITO) coatings were made using an ITO slurry and an ITO sol. This was achieved by dispersing nanosized ITO powder in a mixed solvent without any dispersant and developing an adhesive ITO sol from indium acetate and tin tetrachloride in a mixture of DMF and n-butanol. Coating was carried out in one step by spin coating an ITO slurry, which was then followed by an ITO sol over it. Here, the sol penetrates into the nano ITO particle layers to make them adhere to each other as well as to a glass substrate. This is then followed by sintering at 500℃ for 1 h to produce a uniform film consisting of ITO particles of about 50 nm and 10 nm. ITO films were obtained with sheet resistances from 450 to 1500 ohm/□ by varying spin speed and concentration. Transmittance is higher than 90% at 550 nm.

Preparation and characterization of transparent/conductive nano-composites films

Polymer-embedding of nano-sized indium tin oxide (SnO·In2O3, ITO) produces electrically conductive materials transparent to the visible light at filling factors higher than the percolation threshold. ITO powders are commercially available in an aggregated form and a disaggregation technique was required. Here, aggregated ITO nanoparticles were transformed to colloidal suspension by high-speed stirring. This finely dispersed ceramic suspension was stabilized by addition of poly(vinyl pyrrolidone) and the obtained colloidal system was cast on an optical-grade substrate (PET) to produce electrically conductive-transparent nanocomposite films. Preliminary mechanical and electrical characterization of these films showed good conductivity and interfacial properties.

The Synthesis of Indium Tin Oxide Nano – Powders by Solvothermal Process

Well-crystallized and nano-sized indium tin oxide (ITO) powders were prepared by a solvothermal process from a mixed solution consisting of indium nitrate and tin chloride. The characteristics of the solvothermally synthesized ITO powders were studied to investigate the contribution of the processing variables on the physico-chemical properties of powders. The results of this study show that the nano-sized blue ITO powders with a single phase could be directly obtained by changing the medium from water to organic solvent.

Synthesis of Nano ITO Powders Prepared by Solvothermal Process

In order to provide higher driving forces for densification of Indium-Tin oxide(ITO) sputtering targets, nano-sized ITO powders with uniform size distribution were prepared by solvothermal process. In this study, sintered bodies were densified by a spark plasma sintering (SPS) process at 950 oC. The experiments conduct the SPS method in order to achieve the highest density of sputtering targets. The phase and relative density of ITO sputtering targets were identified by X-ray diffractometry_(XRD) and Archimedes method, respectively. The surface microstructure and quanitative analysis of the targets were observed by scanning scanning electron microscopy (SEM), and ITO powders particle were measured by SEM, XRD-LB methods.

Preparation of Nano-sized Indium Tin Oxide (ITO) Powders and Their Sintering Behavior

In order to fabricate a high density sintered body of ITO, nano-sized ITO powders were synthesized by coprecipitation methods. Aqueous solutions of indium and tin salts were mixed and coprecipitated by changing their pH. Coprecipitated ITO powders possessed 20-30 nm crystallite size and a relatively high BET value (<TEX>$35m^2/g$</TEX>), however, aggregation of particles were occurred. Therefore, a novel recrystallization technique was applied in order to eliminate the aggregates. The recrystallized ITO material consists of a little bit larger needlelike crystals, <TEX>$20nm{\times}80nm$</TEX>, and it possesses a higher BET value <TEX>$(57m^{2}/g)$</TEX> compared to the plain coprecipitated material <TEX>$(35m^{2}/g)$</TEX>. Metastable phase formation and higher content of aggregated particles were observed in the coprecipitated materials. Densification was 95% to 98% complete after 5 hour sintering at <TEX>$1500^{\circ}C$</TEX> for the recrystallized powders while densities of the coprecipitated powders were below 75%.

Solvent effect on synthesis of indium tin oxide nano-powders by a solvothermal process

Well-crystallized and nano-sized indium tin oxide (ITO) powders were prepared by a solvothermal process from a mixed solution consisting of indium nitrate and tin chloride. The characteristics of the solvothermally synthesized ITO powders were studied to investigate the contribution of the processing variables (solvent, working temperature, working pressure) on the physico-chemical properties. The results of this study show that the nano-sized blue ITO powders with a single phase could be directly obtained by changing the medium from water to organic solvent. Comparison of the yellow ITO powders synthesized by the coprecipitation using calcination of precipitates and blue ITO powders synthesized by the solvothermal process indicated that the solvothermal process led to an in situ reduction reaction. Solvent viscosity in the solvothermal process strongly influences both electrical and optical properties of ITO materials for transparent conducting oxides (TCOs). The size of synthesized ITO particles increased with increasing solvent viscosity due to steric hindrance. Moreover, the shape of the synthesized ITO particles became more square with increasing solvent viscosity, because the preferred orientation of ITO materials for crystallization is the fastest in the 〈1 0 0〉 direction.

Densification of nanocrystalline ITO powders in fast firing: effect of specimen mass and sintering atmosphere

Nano-sized indium tin oxide (ITO) powders were prepared by a coprecipitation method, and the sintering characteristics in fast firing were examined. The mass of the specimen, sintering atmosphere and sintering temperature varied. Oxygen atmosphere promoted the densification in normal rate sintering, while oxygen inhibited the densification in fast firing. Fast firing severely retarded densification as the mass of the specimen and the sintering temperature increased. This was explained by differential densification, which could easily occur in conditions with a high densification rate and a high thermal gradient in the specimen, where the outer region of the specimen densifies much faster than the center. Once the highly densified outer skeleton is formed, the inside of the specimen is difficult to densify because the outer skeleton geometrically constrains densification.

Preparation and property control of nano-sized indium tin oxide particle

Indium tin oxide (ITO) particles of 20–30 nm in diameter, which would be used as coating material for electromagnetic wave shield, were synthesized by co-precipitation of indium chloride and tin chloride. Size and shape of particles were controlled by pH of co-precipitation solution, thermal oxidation temperature and tin contents. The prepared particles were thermally reduced under hydrogen gas to control electrical properties. When the solution pH was 6.75, plate type of particles with 60 nm size was coexisted with spherical particles of 20 nm size and the part of crystal structure was hexagonal. As pH was increased, plate type of particles was disappeared and 20–30 nm size of spherical particles were formed. Size of ITO particles was increased and particle resistance was decreased with increasing thermal oxidation temperature of indium tin hydroxide in the range of 400–700 °C. Particle size was decreased as tin content was increased from 3.18 to 21.11 at.% Sn/In in co-precipitation. The resistance of particles had a minimum point with changing of tin contents. The lowest resistance was shown in the region of about 3–5 at.% Sn in ITO. It was confirmed by Auger electron spectroscopy (AES) that tin ratio of ITO particle was increased with increasing tin contents.

Preparation and property control of nano-sized indium tin oxide particle

Indium tin oxide (ITO) particles of 20–30 nm in diameter, which would be used as coating material for electromagnetic wave shield, were synthesized by co-precipitation of indium chloride and tin chloride. Size and shape of particles were controlled by pH of co-precipitation solution, thermal oxidation temperature and tin contents. The prepared particles were thermally reduced under hydrogen gas to control electrical properties. When the solution pH was 6.75, plate type of particles with 60 nm size was coexisted with spherical particles of 20 nm size and the part of crystal structure was hexagonal. As pH was increased, plate type of particles was disappeared and 20–30 nm size of spherical particles were formed. Size of ITO particles was increased and particle resistance was decreased with increasing thermal oxidation temperature of indium tin hydroxide in the range of 400–700 °C. Particle size was decreased as tin content was increased from 3.18 to 21.11 at.% Sn/In in co-precipitation. The resistance of particles had a minimum point with changing of tin contents. The lowest resistance was shown in the region of about 3–5 at.% Sn in ITO. It was confirmed by Auger electron spectroscopy (AES) that tin ratio of ITO particle was increased with increasing tin contents.

Fabrication of Thin Film Using Nanosized Indium Tin Oxide (ITO) Powder and Its Degradation Characteristics

Nanosized ITO powder was fabricated by homogeneous precipitation which used formamide as a precipitator. ITO thin film was deposited by RF magnetron sputtering using ITO target which was prepared by sintering of nanosized ITO powder. From the accelerated degradation test with stress factor of temperature, the lifetime estimate, degradation rate/degree, activation energy and etc. were calculated. It was showed that under thermal condition, the prominent failure mechanism of degradation was the decrease of oxygen vacancies due to oxidation of ITO thin film.

Effects of Crystal Structure and Particle Size on Ethanol Gas Sensing Characteristics of Nanocrystalline ITO Thick Film

Indium tin oxide (ITO) films are widely used in optical devices for their high electrical conductivity and high transparency to visible light. Some relevant papers reported ITO thin films showed favorable sensitivity to NO2 and NO gases. However, researches on gas sensing with ITO films, especially thick films, had not been actively conducted until now. The crystal structure and particle size of ITO can be controlled in nanometer accuracy by coprecipitation method. To investigate the effects of crystal structure and particle size of nano-sized ITO powder on gas sensing properties, two kinds of ITO sensors, having cubic and rhombohedral crystal structures with 15 nm particle sizes, were investigated, and three kinds of ITO sensors having 15, 30, and 70 nm particle sizes, with the rhombohedral crystal structure, were investigated. Gas sensing properties were examined in a chamber with dry air (less than 1 ppm humidity concentration) or gaseous ethanol diluted in dry air. ITO gas sensors with the finer the particle sieze have better sensitivity than of large particle size. The sensitivity of ITO thick films were evaluated by sensing of gaseous ethanol.